Why was Lot's wife judged for looking back?

God punishes people for one reason: disobedience.

  And there came two angels to Sodom at even; (Gen 19:1)

I will not debate the question of what or who is an angel.  For the purpose of this answer, let us assume that whomever these two people were, they had authority.

  ...the Lord hath sent us to destroy [Sodom]. (Gen 19:13)

After all the shenanigans in Sodom, the angels decided it was time for Lot to leave, and leave quickly.  They gave him some last instructions:

  And it came to pass, when they had brought them forth abroad, that he said, Escape for thy life; look not behind thee, neither stay thou in all the plain; escape to the mountain, lest thou be consumed.  (Gen 19:17)

There are the commandments and the punishment for disobedience.

Do not look behind you.
Do not stay in the plain.
Escape to the mountain.

Lest thou be consumed.

Lot negotiated a bit, being old and not believing he could live through the run to the mountains, and the angels agreed the he could flee to the town of Zoar instead.  They actually arrived.

  The sun was risen upon the earth when Lot entered into Zoar.  (Gen 19:23)

It was then that Lot's wife made a choice.  She choose to disobey, and she was punished for it.

  But his wife looked back from behind him, and she became a pillar of salt.  (Gen 19:26)

Why Lot's wife looked back is a completely different question.

Why looking back was a big deal is also a completely different question.

But why Lot's wife was punished for looking back is explained in scripture.  She was commanded not to, and told she would be consumed if she did.  She disobeyed and received the indicated punishment.


Does the Eastern Orthodox Church believe in Aerial Toll Houses?

It's a complex issue which might not be addressed completely by this answer right now. But given enough time I'll elaborate more detail to address many aspects related to this controversy in great depth on my next update. For those unfamiliar with the debate between Hieromonk Seraphim Rose and Archbishop Lazarus Puhalo, this might be a good preliminary introduction to Toll Houses controversy within Eastern Orthodox communion.1 As for now I'll provide a support for this view. Later, I'll add a counter argument from those who rejected this teaching. Each sides on this controversy read the same passages from the Fathers but come to two opposite conclusions: Fr. Seraphim herald this teaching as an Orthodox faith while Fr. Lazarus condemn this teaching as a heterodox innovation. The former claim to preserve this faith from the Fathers while the later claim that this novelty is unknown to the Fathers.2

  We believe that the souls of those that have fallen asleep are either at rest or in torment, according to what each has done; — for when they are separated from their bodies, they depart immediately either to joy, or to sorrow and lamentation; though confessedly neither their enjoyment nor condemnation are complete. For after the common resurrection, when the soul shall be united with the body, with which it had behaved itself well or ill, each shall receive the completion of either enjoyment or of condemnation.

  And the souls of those involved in mortal sins, who have not departed in despair but while still living in the body, though without bringing forth any fruits of repentance, have repented — by pouring forth tears, by kneeling while watching in prayers, by afflicting themselves, by relieving the poor, and finally by showing forth by their works their love towards God and their neighbor, and which the Catholic Church has from the beginning rightly called satisfaction — [their souls] depart into Hades, and there endure the punishment due to the sins they have committed. But they are aware of their future release from there, and are delivered by the Supreme Goodness, through the prayers of the Priests, and the good works which the relatives of each do for their Departed; especially the unbloody Sacrifice benefiting the most; which each offers particularly for his relatives that have fallen asleep, and which the Catholic and Apostolic Church offers daily for all alike. Of course, it is understood that we do not know the time of their release. We know and believe that there is deliverance for such from their direful condition, and that before the common resurrection and judgment, but when we know not.

  Patriarch Dositheous of Jerusalem, Council of Jerusalem in 1672, Decree 18.

Some EOs argue that this confession might be influenced by Latin's influence. As I'll later show, such accusations can't be sustained because this synod is accepted by Patriarchal Sees of Constantinople, Serbia, and Moscow. If it's true that Dositheous was influenced by the Jesuits, those Sees wouldn't accept this synod. To make it more complicated I'll go through one by one EO saints and discuss whether or not they teach the doctrine of Toll Houses explicitly:

  Two Nuns, who had both been Abbesses, died. The Lord revealed to me how their souls had been subjected to the aerial tests, how they had been tried and then condemned. For three days and nights I prayed, wretched as I am, entreating the Mother of God for them, and the Lord in His goodness pardoned them through the prayers of the Mother of God; they passed all the aerial tests and received forgiveness through God's mercy.

  Archimandrite Lazarus Moore, St. Seraphim of Sarov: A Spiritual Biography,
  New Sarov Press, 1994.

This is a very controversial subject to discuss. The Orthodoxy of this teaching as it is now stand has not been decided. Personally, as a Byzantine rite Catholic I believe in Toll Houses, especially because Pope St. John Paul II referred to Hieromonk Seraphim of Sarov as a Catholic saint. To keep my neutrality on this subject, on my next update I'll add counter arguments from those who deny Toll Houses. The purpose of this answer is to bring an awareness and to inform Catholics, Orthodox, and Evangelicals alike about this controversy. That it's not true that the idea of purgatory is unique to Latin's theology. As this answer will later show, both East and West do develop this doctrine around the same time period. The Latins dogmatized this teaching at the Council of Florence in 1439 while the Greeks kept it as theological discourse among the Fathers without dogmatizing it.

1 In my next update, I'll include Eastern Catholic and Oriental Orthodox position on Toll Houses.

2 To be neutral in my answer I'll address both sides as thorough as possible. Because some of the debates resolve around the variations between the Greek and Russian texts. I'll try my best to simplify my answer by discussing the most debated texts for brevity.


What is the history of the concept of a "personal relationship with Jesus"?

Summary:  As you noted, the concept of a "personal relationship with Jesus" could be argued from Scripture, but it is certainly not emphasized in any way.  Relationship with God is almost exclusively described in Scripture as a communal experience.  The emphasis on "personal relationship" is a modern emphasis, and is rooted more in Enlightenment thinking than in Scripture.

The Biblical Emphasis

An Individual Death

Every last person matters to God; He wants everyone to be saved, no matter how "bad" they are.  So there is certainly an open invitation to every person - and this has always been emphasized.

However, what many people do not understand is what God is inviting us into.  He is inviting us to die to our self, and live for Him.  This is the "cost" of following Jesus.  This is not "the real you", or "a better you"... this is "a dead you"!  In other words, we are called to shift our focus from ourselves to others.

Most of the individualistic language in Scripture is either used to describe the entry of sinners into the Kingdom, or the rebellion of heretics against the Kingdom, but not life in the kingdom.  (example)

A Communal Life

When we join the Kingdom of God, we become a part of something special.  There are many ways this "something" is described in Scripture.  Here are a few:

A body of interdependent members, with Christ as the head.
A spiritual house made up of many living stones, with Christ as the cornerstone.
A vine with many branches
A fellowship - with one another and with God.

The Biblical picture of life in the Kingdom is far from individualistic; it is one of interdependency - we grow in our relationship with God through one another and with one another.  (example)

The Enlightenment Emphasis

The Rise of Individualism

The Enlightenment drastically changed the way people viewed the world.  One of the most significant shifts in thinking was from a communal focus to an individualistic focus.

  three fundamental ideas ... encompassed everything the Enlightenment would stand for. First among these was individualism, which emphasized the importance of the individual -source

In the secular realm, this shift in focus led to a new emphasis on "individual rights".

"My Personal Relationship"

This global shift in thinking from communal to individualistic also led to a new emphasis in the teaching and evangelism in the churches.  No longer was the believer merely a part of something bigger, suddenly the believer was the central focus.  This minister summarizes it well:

  The spirit of the Enlightenment has blossomed in the late twentieth and early twenty-first centuries... In the church this individualism translates to: "All I need is my Bible and my God. Anything and anyone else is a threat to my freedom." -source

Nowadays, all that matter is "my personal relationship with Jesus."  As long as I have that, I'm OK.

Clarifications

I am not claiming that believers are disconnected from God in any way, or that God is not a "Person" who loves His people intimately.  God is "personal" in many senses of the word, and we are each "individually" invited to come to Him.  However, the individualistic emphasis on "personal relationship" is not rooted in Scripture; The emphasis in Scripture is on an integral, interdependent, communal fellowship with God and all His people.  We grow in Christ together.

I am also not claiming that there never lived a person prior to the Enlightenment who emphasized individualism in the Church... I am simply saying that we can thank the Enlightenment for the prominence of this theme in churches today.


Why (how) does Jesus' coat have no seam?

There is definitely theological significance to the seamless tunic of Jesus, "woven from the top throughout."  Here is a linguistic argument for that significance.

The Greek for John 19:23 (Nestlé-Aland) says εκ την ανωθεν υψαντος δι ολου.  ek ten anothen hupsatos di holou   "From the top woven by entirety", literally.

That same word ανωθεν (anothen, from the top) happens to show up in John 3:7, which says in the KJV, "Marvel not that I said unto thee, "Ye must be born again." The Greek phrase is δει υμας γεννηθηναι ανωθεν.  It-is-necessary you will-be-born again? top?.

Jesus's garment is woven from the top in just one piece. Yet we must be born (again?) (from above?)  Is it possible that the seamless wholeness of the garment is a symbol of the wholeness conferred by baptism?


Does God Answer Every Prayer Asked In Jesus' Name?

What does it mean to pray "in Jesus' name"? Is it a magical formula that guarantees that your prayer will be heard? For example:

Dear God, please give me a new bike and a chocolate cake and a magical telephone and an elephant. Also, please kill all the bad people. In Jesus' name, Amen.

Does that prayer make more sense because it has "In Jesus' name" at the end? No, indeed not. This is the "cosmic vending machine" or "God as Santa Claus" way of understanding God, and it's pernicious and false. God doesn't act like that.
Let's consider instead the connotations of the word name. It doesn't just mean the word "Jesus" in the same way that "lonesomeday" refers to me. It's very much bound up with the identity of the individual. Think, for instance, back to the Old Testament. The supreme revelation of God's nature to the people of Israel came in the giving of his name:

But Moses said to God, ‘If I come to the Israelites and say to them, “The God of your ancestors has sent me to you”, and they ask me, “What is his name?” what shall I say to them?’ God said to Moses, ‘I am who I am.’ He said further, ‘Thus you shall say to the Israelites, “I am has sent me to you.” ’ God also said to Moses, ‘Thus you shall say to the Israelites, “The Lord, the God of your ancestors, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you”: This is my name for ever, and this my title for all generations.’ (Exodus 3.13-16, NRSV)

The name of God is who God is. It is so holy, so bound up with his entire identity, that it is never uttered by Jews. It was uttered just once a year by the High Priest in the Holy of Holies on Yom Kippur. It was immensely powerful because it was not just a word but an identity. Similarly, take Psalm 20:

Some take pride in chariots, and some in horses, but our pride is in the name of the Lord our God.

This isn't saying "we're proud that our God is called YHWH", but "our pride comes from who our God is".
This is the sense that "name" is used in the Gospel of John. It's actually used on a whole host of occasions. Here are a few of them to give a suggestion of what it connotates:

But to all who received him, who believed in his name, he gave power to become children of God (John 1.12)
Those who believe in him are not condemned; but those who do not believe are condemned already, because they have not believed in the name of the only Son of God. (John 3.18)
I have come in my Father's name, and you do not accept me; if another comes in his own name, you will accept him. (John 5.43)
But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you everything, and remind you of all that I have said to you. (John 14.26)
But they will do all these things to you on account of my name, because they do not know him who sent me. (John 15.21)
"I have made your [i.e. the Father's] name known to those whom you gave me from the world. (John 17.6)
But these are written so that you may come to believe that Jesus is the Messiah, the Son of God, and that through believing you may have life in his name. (John 20.31)

Beyond this, we might also point to the occasions where Jesus alludes to the name of God in his speech, such as 8.58: ‘Very truly, I tell you, before Abraham was, I am.’
These give, I think, a bit of a picture of what "Jesus' name" is referring to in John. It refers precisely to Jesus' identity and his purpose. "Jesus' name" is who Jesus is. And we know from the prologue to the Gospel that Jesus is "the Word made flesh". He is the one who has "made God known".
So when we pray "in Jesus' name" we are praying "according to who Jesus is", that is to say according to his nature as the revelation of God; the salvation of his people; the way, the truth and the life; the gate of salvation. We are praying according to who Jesus most fundamentally is. To pray in Jesus' name is to conform ourselves to that identity.
What does it mean, then, to ask for something in Jesus' name? I don't know precisely. But it is rooted in our Christian knowledge of who Jesus is. It is connected intimately to the fact of our salvation. It isn't a separate magical formula that gets us a special hearing.

Andrew Lincoln wrote an chapter on this subject, entitled "God's name, Jesus' name, and prayer in the fourth gospel". It can be found in a book entitled Into God's Presence: Prayer in the New Testament. I'm afraid I don't have a copy, but I read it a little while ago and it is excellent.


Giving a name while doing circumcision?

Catholics celebrated the Feast of the Circumcision on January 1st up until Vatican II.

  The Feast of the Circumcision of Christ is a Christian celebration of the circumcision of Jesus in accordance with Jewish tradition, eight days (according to the Semitic and southern European calculation of intervals of days) after his birth, the occasion on which the child was formally given his name.

  The circumcision of Jesus has traditionally been seen, as explained in the popular 14th-century work the Golden Legend, as the first time the blood of Christ was shed, and thus the beginning of the process of the redemption of man, and a demonstration that Christ was fully human, and of his obedience to Biblical law.

  The feast day appears on 1 January in the liturgical calendar of the Byzantine Catholic and Eastern Orthodox Churches.[4] In the General Roman Calendar, the 1 January feast, which from 1568 to 1960 was called "The Circumcision of the Lord and the Octave of the Nativity", is now named the Solemnity of Mary, Mother of God, and the Octave Day of the Nativity of the Lord. It is celebrated by some churches of the Anglican Communion and virtually all Lutheran churches. In these latter Western Christian denominations, the Feast of the Naming and Circumcision of Jesus Christ marks the eighth day (octave day) of Christmastide. - Feast of the Circumcision of Christ

The biblical basis for such a feast comes from the Gospel of Luke:

  21 And at the end of eight days, when he was circumcised, he was called Jesus, the name given by the angel before he was conceived in the womb. Luke 2:21

We can see that Scriptures indeed noted down that this was in fact an historical Jewish custom.

Other biblical references include the following:

  59 And on the eighth day they came to circumcise the child. And they would have called him Zechariah after his father. -Luke 1:59

  12 He who is eight days old among you shall be circumcised. Every male throughout your generations, whether born in your house or bought with your money from any foreigner who is not of your offspring. - Genesis 17:12

  22 Moses gave you circumcision (not that it is from Moses, but from the fathers), and you circumcise a man on the Sabbath. 23 If on the Sabbath a man receives circumcision, so that the law of Moses may not be broken, are you angry with me because on the Sabbath I made a man's whole body well? - John 7:22-23


What is the scriptural basis, if any, for the Catholic teaching that the homosexual tendency is of itself not a sin?

The Catholic teaching that the homosexual tendency is not a sin is based on the universal principle that sin requires the use of the will--you cannot sin by accident.  See ST II I, q. 71, a. 5, objection & reply 2; ST II I, q. 75, a. 2 & 3; and CCC 1849-1851.

This is a commonsensical principle of human responsibility that is presupposed by scripture (and every legal system in the world).  Although, like many other such principles, scripture does not philosophically define this relation of will/volition to sin, we can see it underlying scriptural passages in many places.  For example:

Joshua 20:1-9 illustrates the mitigation of sin and culpability when someone causes a death by accident.
2 Corinthians 5:10 says that we will be judged for what we do.  Personal action is involved in sin and judgment, and personal action requires an act of the will.
Without knowing and willing what one is doing, sin cannot exist (Romans 5:13, Romans 7:7).
Jesus asks that his executioners be forgiven and provides only one reason: they do not know what they are doing (Luke 23:34).


What is the origin of praying hands folded?

Very interesting question. I did some browsing and came up with the following information.

First of all, this link has some content on the topic:

http://answers.google.com/answers/threadview/id/271624.html

Here is one quote from that thread, but I recommend reading it and judging the content for yourself:

  The Talmud relates how the Babylonian Sage, Rabba (Abba ben
  Joseph, C. 280-352), used to pray with his hands folded.

So "folding hands" could have come down from the Jewish heritage of Christians. Others also distinguish between "praying hands" and "folding hands".

And for the meaning of it, I came across the following web page:

http://www.stjosephsite.com/SJS_Articles_prayinghands.htm

It mentions the following information (pasted in fragments):

  Such a prayer gesture is a symbol of obedience, submission, sincerity and repentance.

  ...

  Nathan Ausubel, in his book "Book of Jewish Knowledge said that this prayer gesture is not exclusive to Christians alone. He said the Jews even before the time of Jesus Christ, practiced it: "It has also been commonly assumed that folding the hands in prayer is exclusively a Christian custom. This is not the historical fact at all. As early as the post-Exilic period, when Jews prayed, they folded their hands, and they observed this custom for several centuries even after it had been adopted by Christians."

  Jesus, being a Jew, also prayed with clasped hands. You must have seen pictures or images of Him in the garden of Gethsemani in this prayer gesture. In other art works, you can also see the Virgin Mary and angels with their hands clasped as well.

  ...

  The Pope mentioned the custom during feudal times of placing one's joined hands into the hands of his ruling lord as a sign of his fidelity and loyalty. So when we fold our hands in prayer, we are symbolically pledging to God our fidelity and loyalty and placing our hands in His.

And another viewpoint here:

http://www.trivia-library.com/a/why-does-a-person-join-his-hands-when-praying.htm

  The joining of hands "leads back to men's early desire to subjugate each other and developed out of the shackling of hands of prisoners!

  "Though the handcuffs eventually disappeared, the joining of hands remained as a symbol of man's servitude and submission and his inability (or even lack of inclination) to grasp a weapon."

  Christianity adopted "the gesture representing shackled hands as a sign of man's total obedience to divine power."

Another reference (and a selective quote from it):

http://www.answerbag.com/q_view/421928

  "Religious historians trace the gesture back to the act of shackling a prisoner’s hands with vine or rope: joined hands came to symbolize submission. In ancient Rome, a captured soldier could avoid immediate death by joining the hands together. Just as waving a white flag today, the message was clear. “I surrender.”
  Centuries later, subjects demonstrated their loyalty and paid homage to their rulers by joining their hands. In time, clasping the hands together communicated both an acknowledgement of another’s authority and one’s own submission to that authority."

Books by Nathan Ausubel:

http://www.amazon.com/s/ref=ntt_athr_dp_sr_1?_encoding=UTF8&sort=relevancerank&search-alias=books&field-author=Nathan%20Ausubel


What is the Protestant argument against the doctrine of Purgatory?

Protestants would consistently reject certain things connected to the doctrine of Purgatory. Regarding justification by faith alone: the fate of the dead should not be affected by their own suffering (Christ's atonement being sufficient) nor by the prayers and other works of the living. Moreover, Protestants would not believe in a role for the Church here - in granting indulgences and so forth. All of this comes from the "usual" Biblical basis for those Protestant doctrines, without specifically addressing Purgatory.

If Purgatory is seen only as a place where post-mortem sanctification happens, things are a bit murkier. That is, if we imagine it as merely a necessary cleansing step before dead people can enter heaven, then is there any Biblical argument against it? (Other than the lack of an explicit argument in favour, of course, as the Articles of Religion say: "a fond thing vainly invented, and grounded upon no warranty of Scripture.")

Protestant thinkers have tended to argue that sanctification is completed or consummated by the moment of death. John Wesley, for example, taught that the perfection we seek in life is completed at "the instant of death, the moment before the soul leaves the body" (Brief thoughts on Christian perfection, 1767). If this is so, then there may be a "very brief transition from death to paradise" (The Last Things, Donald Bloesch, 2004) but not a prolonged period of transformation.

This is backed up by such Biblical references as 1 Corinthians 15, where the raising of the dead in their already-perfected bodies is essentially instantaneous, and Jesus' words to the thief on the cross, "Today you will be with me in paradise" (Luke 23:43). N T Wright points to Romans 6:6 as indicating that the death of the body entails the death of sin (For all the saints? Remembering the Christian departed, 2004), and, more importantly, to Romans 8:38-39 for the vivid statement that nothing, even death, "can separate us from the love of God in Christ Jesus our Lord". Surely, he says, there is no separation for the saved after death.

However, these Biblical texts are not absolutely decisive about timescale. Perhaps time is not even a sensible concept here, as in more recent Catholic thought where specific periods of time are not mentioned (Indulgentiarum Doctrina, 1967). But the objections to Purgatory as a place of punishment, and to indulgences remitting punishment, remain even if some kind of post-mortem transformative sanctification process is accepted.


If you accept its own testimony then Luke was written:-

Before the Acts of the Apostles and by the same author as the writer of Acts (compare Acts 1:1 with Luke 1:1-4);

The author of Acts was, at times, a companion of Paul on his missionary journeys:
about 49 AD, Acts 16:10-18;
about 54-57 AD, Acts 20:4-21:19; and
about 59-62 AD, Acts 27:1-28:30.

All these passages are the "we" passages.
There is so much detail in Acts which has been confirmed by archaeology that it has been said that it would need a bigger miracle for it to have been made up than for the author to have genuinely accompanied Paul on his journeys.

Seeing as Paul died about 65 AD it is obviously not possible that Acts was written mid 2nd century.  It seems a compelling argument to me and many others that Acts was written before certain events which would have been included in it if it had been written later.  These events include possibly:
The death of Paul, the death of Peter, the death of James the first Pastor of the church at Jerusalem 62 AD; the first Jewish Roman War 66-70 AD; the change in attitude of the Roman authorities towards Christianity with the beginning of the Roman persecutions under Nero; the Great Fire at Rome.

The most natural explanation why these events are not included in Acts is that Acts was written before these events.
What Acts presents is the prevailing situation before Nero.  The persecutors of the church were the Jewish authorities who struggled to get the Roman authorities to be interested in trying to suppress the new "sect".

The author of Luke claims to have "had a perfect understanding of all things from the very first" Luke 1:3.  In other words he is claiming that he is in a perfect position, he is ideally qualified to tell Theophilus the history of the events from his perspective, making use of eyewitness accounts.

The author is at pains to warn his readers of the coming destruction of Jerusalem, that when they see certain things happening then they should flee from Jerusalem. (Jerusalem was destroyed at the end of the Jewish-Roman War, 66-70 AD.)  Obviously such warnings are superfluous and disingenuous if Jerusalem has already been destroyed.  On this understanding Matthew, Mark, and Luke were written before 66 AD and John's Gospel was written after 70 AD.

Supporting such a view, in 1972, a Spanish-Catalan Jesuit scholar, Father Jose O'Callaghan of Barcelona claimed that the Dead Sea Scroll papyrus 7Q5 was a fragment of Mark's Gospel, it was from Mark 6:53.  Seeing as the community at Qumran was destroyed by the Romans about 66 AD this means that Mark's Gospel must have been written before 66 AD.  In other words 7Q5 is evidence of the early authorship of at least Mark's Gospel.  And if Mark could predict the coming destruction of Jerusalem then why not Luke and Matthew?

The dismissal of scholars of the possibility of Matthew, Mark, and Luke being written before the destruction of Jerusalem betrays a fundamental failure on their part to appreciate that this prediction of our Lord could have easily been a product of his understanding of the Old Testament.  The prediction of the destruction of Jerusalem is not merely in these three gospel accounts: it is also found in the book of Daniel:

and after three score and two weeks shall the Messiah be cut off, but not for himself: and the people of the prince shall come and destroy the city and the sanctuary, and the end thereof shall be with a flood (i.e. "an overwhelming")... Daniel 9:26.

Though conservative evangelicals would say it was written about 535 BC, even the generally accepted date for the writing of Daniel amongst "the scholars" is about 165 BC.  There were many portions of the book of Daniel found amongst the Dead Sea Scrolls dateable to more than 100 BC.
There is no compelling reason to suppose the three Synoptic Gospels were written after the destruction of Jerusalem.  Our Lord could have been merely quoting the book of Daniel.
For more on 7Q5 see "The Jesus Papyrus" by Carsten P. Thiede and Matthew D'Ancona or "The First New Testament" by David Estrada and William White.
Finally, a related question and answer is found here:  Who assigned the gospel authors originally?


Is there any methodology according to Bible to drive out demons from possessed people?

Acts 16:18 (NIV)  She kept this up for
  many days. Finally Paul became so annoyed that he turned around and
  said to the spirit, “In the name of Jesus Christ I command you to come
  out of her!” At that moment the spirit left her.

Apostle Paul cast out the evil spirit by using the name of Jesus Christ. Anyone who believes Jesus Christ is given the power to drive out demons by faith and prayer.

  Mark 16:16-18 (NIV) Whoever believes and is baptized will be saved,
  but whoever does not believe will be condemned. And these signs will
  accompany those who believe: In my name they will drive out
  demons; they will speak in new tongues; they will pick up snakes
  with their hands; and when they drink deadly poison, it will not hurt
  them at all; they will place their hands on sick people, and they will
  get well.”

Some evil spirits are so powerful that it require more prayer and faith.

  Mark 9:29 (NIV) He replied, “This kind can come out only by prayer.”

As we can see in these verses, it's quite simple. It only require faith and prayer followed by pronouncing the name of Jesus Christ. But the most problematic here is having faith, which can be achieved through prayer and experience only. I myself once participated in an exorcism performed by our pastor. All we did was pray, sing songs and command the evil spirit to come out in the name of Jesus Christ, and it worked :-)

The methodology is simple. Prayer, Fasting and Commanding in the name of Jesus Christ. But it is not easy. Method is simple, but not easy to carry it out. It needs a lot of faith, personal relationship with God and patience.


Protestants and Sola Scriptura adherents: When was scripture alone sufficient?

There is a picture of the Bible being sufficient given in the parable of the rich man and Lazarus.

  Luke 16:31  And he said unto him, If they hear not Moses and the
  prophets, neither will they be persuaded, though one rose from the
  dead.

We see that even the Old Testament was sufficient for one to be inclined to receive Jesus.

  John 5:46  For had ye believed Moses, ye would have believed me: for
  he wrote of me.

The Old Testament was sufficient for people to hear about God and his promise and to trust in that promise.

  Hebrews 11:6  But without faith it is impossible to please him: for he
  that cometh to God must believe that he is, and that he is a rewarder
  of them that diligently seek him.

  Hebrews 11:32  And what shall I more say? for the time would fail me
  to tell of Gedeon, and of Barak, and of Samson, and of Jephthae; of
  David also, and Samuel, and of the prophets:


What are the sources concerning the deaths of Peter and Paul

John Foxe, in his 'Book of Martyrs', 1563, catalogues his sources regarding the martyrdom of Paul and Peter.

Of the recorded history of Paul's death, Foxe quotes :

  Eusebius, Hierom, Maximus, and other authors do but briefly pass it over; so Abdias, (if his book be of any substantial authority,). . . .

Of the sources of the record of Peter's death, he says . . .

  Hierom, Egesippus, Eusebius, Abdias, and others, although they do not all precisely agree in the time.

So it would seem that there are limitations in the availability of verifiable historic material.


To add to the other answers given here, in the Catholic liturgy (Mass, Liturgy of the Hours), it is common to address the saints as “blessed.” It is not exactly a title, but a term of respect that recognizes their condition of beatitude in Heaven.

For example, the Roman Canon (Eucharistic Prayer I) says two paragraphs before the epiclesis (the invocation of the Holy Spirit), “In communion with those whose memory we venerate, especially the glorious ever-Virgin Mary, [...] blessed Joseph, her Spouse, your blessed Apostles and Martyrs [...].” It is similar with the Blessed Virgin Mary.

Similarly, on memorials and feast days of saints, whenever the saint is referred to in a prayer, he is addressed as “blessed” (beatus or beata). Here, for example, is the collect for today’s feast (July 3), the feast of St. Thomas the Apostole:

  Grant, almighty God,
  that we may glory in the Feast of the blessed Apostle Thomas,
  so that we may always be sustained by his intercession
  and, believing, may have life
  in the name of Jesus Christ your Son,
  whom Thomas acknowledged as the Lord.
  Who lives and reigns with you in the unity of the Holy Spirit,
  one God, for ever and ever.

That is probably the most direct reason that in English we have tended to use the term “Blessed Virgin Mary” rather than “Saint Mary.” As Raphael Rosch pointed out, in many other languages (especialy Romance languages), the etymologically equivalent word for “saint” simply means “holy,” and so it is more commont to hear expressions such as “Sainte Marie” or “Santa Maria.”


Does "Mere Christianity" represent the core of Christian belief?

This is what Lewis has to say for himself in his introduction:

I hope no reader will suppose that "mere" Christianity is here put forward as an alternative to the creeds of the existing communions—as if a man could adopt it in preference to Congregationalism or Greek Orthodoxy or anything else. It is more like a hall  out of which doors open into several rooms. If I can bring anyone into that hall I shall have done what I attempted. But it is in the rooms, not in the hall, that there are fires and chairs and meals. The hall is a place to wait in, a place from which to try the various doors, not a place to live in. For that purpose the worst of the rooms (whichever that may be) is, I think, preferable.

Lewis (along with contemporaries such Dorothy L. Sayers and Dietrich Bonhoeffer) played a part in promoting the Ecumenical movement and struggled with the definition of the Church.  On the one hand, philosophically there ought to be a unifying system of belief among the body of Christ.  On the other, many of us find life in the beliefs and practices that are most divisive.  (Depending on which side of the Adriatic Sea you live on, Hesychasm is either "navel-gazing" or experiencing God.)
Mere Christianity proposes a solution that we simply ignore those things we disagree on and talk about those that are common.  To use Lewis' analogy of a large building with many rooms, the hallways will have beige carpet and unobjectionable artwork and plants that don't require much in the way of care.  In the same way, "mere" Christianity will insist on only those beliefs and practices that remain when the bulk of disagreement is removed.
Shockingly, what's left over turns out to be supremely rich.

After a paragraph in which he explains that some people may spend considerable time in the hallway before finding (what we Protestants sometimes call) a "church home", Lewis address picking a denomination and how we should think of those we disagree with:

In plain language, the question should never be: "Do I like that kind of service?" but  "Are these doctrines true: Is holiness here?  Does my conscience move me towards this? Is my reluctance to knock at this door due to my pride, or my mere taste, or my personal dislike of this particular door-keeper?"
When you have reached your own room, be kind to those who have chosen different doors and to those who are still in the hall. If they are wrong they need your prayers all the more; and if they are your enemies, then you are under orders to pray for them. That is one of the rules common to the whole house.

Summary
More than anything else, Mere Christianity stands as a valiant attempt at ecumenicism.  If it fails, it fails because the idea of bringing the entire Christian faith into one house is unworkable.  I would prefer to believe that it succeeds.


What is closest thing Baptists have to a catechism?

In fact, Baptists do have a catchecism.  As John Piper writes here:

  Written in 1677, "The Baptist Catechism" was patterned after the Heidelberg and Westminster catechisms to teach Reformed doctrine from a Baptist perspective.

The problem isn't the existence, but rather how many Baptists are willing to "cede my author-ITAY" (imagine your best Cartman voice) and use it...

That said, if a Baptist is going to trust anybody, John Piper is a pretty good modern bet, and the 1677 Heidleberg & Westminster Confessions, from which Piper draws all his source material, is about as good as one can get.  As far as being "trusted" then, it definitely suits the bill.  Again, your primary problem in declaring "a" Baptist anything, however, is that there is a native distrust of anything that exists outside of the local congregation, hence the waffling.

Finally, John Piper has very solid evangelical credentials, so its applicability to "nondenominational" churches should be a good bet.  As just two data points (and with evangelicals that's about as good as your going to get), I was turned on to Piper by Mike Minter, the pastor of Reston Bible Church (approximately 4000 in regular attendance) and have heard similar endorsements from Lon Solomon, pastor of McLean Bible Church, the 17th largest church in the United States.  Both of these should qualify.


How does LDS doctrine reconcile monotheism with men becoming gods?

I suppose if you wanted to split hairs, you could technically consider the LDS faith to be polytheistic, since Mormons believe God the Father, God the Son, and God the Holy Ghost to be separate and distinct individuals.

Outside of that, it's pretty simple.  Mormons worship God the Father, through the Son.  While we believe that there are other gods out there, they are not our God.  I find that an analogy helps me think about this clearly: At work, I have one boss.  He is my boss and no one else is.  There are other bosses, but I do not report to them, they do not affect my quarterly reviews, and I don't really interact with them in any sort of manager-underling relationship.  The same goes for God.


What kind of star was shining when Jesus was born?

The Star which led the wise men was a new Heavenly body.
Matthew chapter 2:KJV

2  Saying, Where is he that is born King of the Jews? for we have seen his star in the east, and are come to worship him.
7  Then Herod, when he had privily called the wise men, enquired of them diligently what time the star appeared.

The Star may not have been a Star, but a (messenger of God) which shined like a Star.
Matthew 2:9  KJV

When they had heard the king, they departed; and, lo, the star, which they saw in the east, went before them, till it came and stood over where the young child was.

Whatever it as it could not have been a Star as we know them since to us a Star is actually a distant Sun, and this Star was low enough that it could guide them and move to where Jesus was. The wise men may have deemed it a Star for lack of any other descriptive of it's phenomena.
It should also be noted that King Herod asked them when the Star appeared, and if that Star were to have appeared where it could be seen by everyone, why was Herod not aware of it.
The Bible does not tell us that the Shepherds saw the Star:
Luke chapter 2:9 through 18 KJV

9  And, lo, the angel of the Lord came upon them, and the glory of the Lord shone round about them: and they were sore afraid.
10  And the angel said unto them, Fear not: for, behold, I bring you good tidings of great joy, which shall be to all people.
11  For unto you is born this day in the city of David a Saviour, which is Christ the Lord.
12  And this shall be a sign unto you; Ye shall find the babe wrapped in swaddling clothes, lying in a manger.
13  And suddenly there was with the angel a multitude of the heavenly host praising God, and saying,
14  Glory to God in the highest, and on earth peace, good will toward men.
15  And it came to pass, as the angels were gone away from them into heaven, the shepherds said one to another, Let us now go even unto Bethlehem, and see this thing which is come to pass, which the Lord hath made known unto us.
16  And they came with haste, and found Mary, and Joseph, and the babe lying in a manger.
17  And when they had seen it, they made known abroad the saying which was told them concerning this child.
18  And all they that heard it wondered at those things which were told them by the shepherds.

Since the birth of Jesus was such an Earth changing event it seems to me that announcing with a shining Angel would fit just right with what I know of God


Why doesn't dispensationalism identify a dispensation focused on David?

Dispensation can be understood as "a distinctive arrangement or period in history that forms the framework through which God relates to mankind".  Under both the Judges and the monarchy period (including David's dynasty), the judges & kings are "state" authorities charged with secular implementation of the framework necessary for the priestly system and the constitutional (the Torah) system to operate.  David would then fall under the yellow "Human Government" box in your diagram.

I would compare Israel / Judah king's role at that time to how a Christian Roman emperor (like Constantine or Justinian) or the King of England see their role in giving the Church with proper secular support and secular powers to exert her spiritual authority, just like God expected the Israel / Judah kings to build and support the temple, to support the right judicial authorities, and to cry out only to Yahweh for help during times of invasions / famine, etc.  But we read in the books of Samuel, Kings, and Chronicles how with the exception of David the kings compromised their duties from little (like Josiah, Hezekiah) to huge (like Ahab).  They are supposed to destroy foreign god's temple and to implement justice (Torah) but INSTEAD they import foreign gods or by not going far enough to destroy foreign god worship erected by their predecessors.  So God responded in the same degrees: respectful burial for Josiah / Hezekiah, relatively minor troubles for them during their lifetime, but total humiliation and the end of his dynasty for Ahab, culminating in the 2 exiles under Assyria and Babylon.

After returning from exile under Persia, throughout the second temple period, some (most?) Jews expected two kinds of Messiah: a priestly one coming from the line of Moses (Levite), and a Davidic one.  Jesus was both, even though Jesus descended from David.  I think that is why the book of Hebrews justified Jesus's office as Priest by saying that his priesthood was from the order of Melchizedek (because He was not Levite by blood).  It is Jesus's Priesthood which is part of dispensation, hence the purple Grace box in the diagram.  But Jesus is also King, the King of Christendom until today, continuing until the second coming, but this authority falls under "Human Government" (yellow box).

So yes, David was a big deal, and so is Jesus's authority as King today!  All countries's supreme authorities dominating the news recently, whether it's US President, Canada Prime Minister, King of England, Japanese emperor, Saudi King, Thai King,  Chinese communist party, President of Russia, should all submit to Jesus's authority as King in the yellow box to give room and support for the Church, for example by defending her existential rights, her secular rights, her input to the country's laws, and police protection against violence.

But dispensation is essentially about our relationship with God, administered in the current dispensation through Grace (applied directly to individuals for Protestants, or through the sacraments of the church for Catholics), and I think that's why David didn't get a separate marker in the diagram but he definitely belonged to the yellow box and all authorities of the world today should look at David for role model.

Now to answer your specific points:

  The monarchy represents a major shift from a judge/prophet-led and distributed nation to a centralised king-led nation, and from the priests being the people's sole representatives before God to the king also being their represenative.

I would not call David as God's representative, but as God's choice (as in God chose David over Saul).  In the monarchical period I believe the King was supposed to be anointed and coronated by a priest, God's true representative.  When a king needs to seek God's help the king needed to go to the Temple, a precinct of the priesthood.  So a King didn't have inherent access to God, unlike a priest.  God also used prophets as official messenger, the "mouthpiece" of God, and the King was supposed to listen and obey.  But prophets do not have stable, permanent office like a priest, and anyone (non-Levite) can be called to serve as a prophet.  The Pharisees and Sadducees were fine with Jesus if he restricted his activity as a prophet, but Jesus made bigger claims.

  David's covenant is one of the few Biblical covenants, the others (Noah, Abraham, Moses and Phinehas, the New) are associated with the beginning of dispensations.

Remember that David's covenant is not the same as Mosaic / Sinai covenant, and is not the same as Abrahamic covenant.

David's covenant is personal (to David alone, the man after God's heart), and God fulfilled it in Jesus who now rules forever.  It's a done deal; there is no more to be expected.
But people are not saved by David's covenant, people are saved through the Mosaic covenant (the cyan "Law" box), also a done deal since Jesus fulfilled the Law.
Abrahamic covenant is also different in kind, having to do with "physical stuff": descendants, prosperity, and a means to lead Gentiles to God (some would say that's why God is preserving the Jewish people as a race).

So it's best not to confuse covenant with dispensation.


What are the major differences between Eastern and Western Orthodox Christianities?

Big question!  Here is my source:

  The culture - The East is familiar to Greek, Russian and Arabic
  languages/cultures, and the West is more familiar to Americans and
  English languages/cultures
  The Clergy Vestments
  The Liturgy/Mass - The
  East primarily uses the Liturgy of Saint John Chrysostom, and the West
  primarily uses the Liturgy of Saint Gregory the Great.
  The East has an
  Iconostasis ("Icon Wall") separating the Sanctuary from the rest of
  the church, and the West either has a rail (like the old Roman
  Catholic style) or nothing at all separating the Sanctuary from the
  rest of the church


What is the earliest claim that Jesus Christ kept the law of Moses on behalf of others?

This is the earliest extra-biblical clear statement I have found so far.

Christ therefore ransomed from the curse of the law those who being subject to it, had been unable to keep its enactments. And in what way did He ransom them? By fulfilling it. And to put it in another way: in order that He might expiate the guilt of Adam’s transgression, He showed Himself obedient and submissive in every respect to God the Father in our stead… - St. Cyril of Alexandria (378 – 444 AD) – Commentary on Luke

1 Peter 3:18 "For Christ also suffered once for sins, the righteous for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit," is a more indirect declaration wherein one must make the leap that he was righteous by keeping the Law.


Was the Trinity looked upon by John of Damascus and Gregory of Nyssa as a combination of Jewish monotheism and pagan polytheism?

TL;DR: When the 3 quotes are considered in proper genre and context they fail to support OP's argument.

First, it is helpful to distinguish the following 3 angles when reading the Church Fathers talking about the Christian dogma of Trinity.  (The section references mentioned below are from the Catholic encyclopedia entry "The Blessed Trinity")

Revelation: The "raw data", solely from how God revealed himself in the OT, in Jesus and in manifestations of the Holy Spirit, as recorded in the New Testament by different authors such as St. John, St. Paul, etc.

Without this revelation there is nothing to go by.
That is why we often speak of Trinity as "The Mystery of the Trinity".
This is 100% God initiated action, which is why for Christianity any proper understanding of the Trinity should not say more than what NT says.
See "Dogma of the Trinity" and "The Trinity as a mystery" sections.

Usage in the church: How Trinity is implied in baptism, doxologies, theologies, catechism, apologetical writing, refuting heresies, etc.

Through the writings we see how the Church Fathers appeal only to the New Testament as the source of their teaching of the dogma.
Language precision is not necessary, but appeal to NT is a must.
Greek philosophical concepts are sometimes used to assist in describing but not as a source for the dogma.
See "Proof of the doctrine from Scripture" and "Proof of the doctrine from Tradition" sections.

Language refinement: Development of how Trinity is defined in various Greek and Latin theologies by the Church Fathers, development of the formulas in the creed, etc.

This is where Greek philosophical concepts and language became critical, to the point of some philosophically inclined Church Fathers having to stretch existing terminologies or even invent new ones.
Borrowing Greek terminologies & concepts is like a physicist (Church Father) needing to describe his/her experiment using mathematical language.  A mathematician (Greek philosopher) has no expertise in conducting the experiment, so proper credit belongs to the physicist.
100% for description, not for the source (which is only NT).
Underlying mystery is still maintained.  That is why for practical purposes, inability to define Trinity completely (in philosophical language) is unnecessary for belief, because God cannot be reduced to a formula.
The goal for definitions (used in the creeds) is for easy refutation of heresies.
See "The doctrine as interpreted in Greek theology" and "The doctrine as interpreted in Latin theology" sections.

Now responding to your 3 quotations.  All of them need to be interpreted in context according to the proper genre of the work.

St. Gregory of Nyssa's The Great Catechism (c. AD 385) Chapter III, pdf here

The genre is Angle #2 above (usage in the church), for apologetic/catechical (teaching) purpose to explain the faith to the educated Greek speaking intelligentsia.
Full text of Chapter III for context:

  AND so one who severely studies the depths of the mystery, receives secretly in his spirit, indeed,
  a moderate amount of apprehension of the doctrine of God’s nature, yet he is unable to explain
  clearly in words the ineffable depth of this mystery. As, for instance, how the same thing is capable
  of being numbered and yet rejects numeration, how it is observed with distinctions yet is apprehended
  as a monad, how it is separate as to personality yet is not divided as to subject matter. For, in
  personality, the Spirit is one thing and the Word another, and yet again that from which the Word
  and Spirit is, another. But when you have gained the conception of what the distinction is in these,
  the oneness, again, of the nature admits not division, so that the supremacy of the one First Cause
  is not split and cut up into differing Godships, neither does the statement harmonize with the Jewish
  dogma, but the truth passes in the mean between these two conceptions, destroying each heresy,
  and yet accepting what is useful to it from each. The Jewish dogma is destroyed by the acceptance
  of the Word, and by the belief in the Spirit; while the polytheistic error of the Greek school is made
  to vanish by the unity of the Nature abrogating this imagination of plurality. While yet again, of
  the Jewish conception, let the unity of the Nature stand; and of the Hellenistic, only the distinction
  as to persons; the remedy against a profane view being thus applied, as required, on either side.
  For it is as if the number of the triad were a remedy in the case of those who are in error as to the
  One, and the assertion of the unity for those whose beliefs are dispersed among a number of
  divinities.

Chapter III is showing how Trinity is the best way to understand the nature of the Christian God (who is still a mystery, by the way, indicated by the 1st sentence).  So here's Gregory of Nyssa affirming the source is Angle #1 (revelation).  The rest of the chapter beginning with "But when you have gained the conception of what the distinction is in these..." is an Angle #3 activity (speculative understanding of the mystery), and Gregory's advice is for the believer NOT to commit an error by straying to the Jewish heresy (not accepting Jesus as the Word), or to the Pagan heresy (by construing the Christian God polytheistically).  There is NOTHING here indicating Gregory of Nyssa saying that the dogma of Trinity is derived from pagan sources.
The year was around 385 AD, after major debates on the formulation of the doctrine (an Angle #3 activity) had been done.

St. John of Damascus (675-749 AD)'s De Fide Orthodoxa (An Exact Exposition of the Orthodox Faith) Book I Chapter VII (Concerning the Holy Spirit, a reasoned proof) pdf here

The genre is traditional Christian theology (Angle #3) deriving mostly from theologians of the 4th and 5th centuries, providing a comprehensive overview of Christian dogma.  Damascene supports his writing through logic and quoting Scripture.  (summary taken from here)
Full Text of Chapter 7 for context:

  Moreover the Word must also possess Spirit. For in fact even our word is not destitute of spirit; but in our case the spirit is something different from our essence. For there is an attraction and movement of the air which is drawn in and poured forth that the body may be sustained. And it is this which in the moment of utterance becomes the articulate word, revealing in itself the force of the word. But in the case of the divine nature, which is simple and uncompound, we must confess in all piety that there exists a Spirit of God, for the Word is not more imperfect than our own word. Now we cannot, in piety, consider the Spirit to be something foreign that gains admission into God from without, as is the case with compound natures like us. Nay, just as, when we heard of the Word of God, we considered it to be not without subsistence, nor the product of learning, nor the mere utterance of voice, nor as passing into the air and perishing, but as being essentially subsisting, endowed with free volition, and energy, and omnipotence: so also, when we have learned about the Spirit of God, we contemplate it as the companion of the Word and the revealer of His energy, and not as mere breath without subsistence. For to conceive of the Spirit that dwells in God as after the likeness of our own spirit, would be to drag down the greatness of the divine nature to the lowest depths of degradation. But we must contemplate it as an essential power, existing in its own proper and peculiar subsistence, proceeding from the Father and resting in the Word , and showing forth the Word, neither capable of disjunction from God in Whom it exists, and the Word Whose companion it is, nor poured forth to vanish into nothingness , but being in subsistence in the likeness of the Word, endowed with life, free volition, independent movement, energy, ever willing that which is good, and having power to keep pace with the will in all its decrees , having no beginning and no end. For never was the Father at any time lacking in the Word, nor the Word in the Spirit.

  Thus because of the unity in nature, the error of the Greeks in holding that God is many, is utterly destroyed: and again by our acceptance of the Word and the Spirit, the dogma of the Jews is overthrown: and there remains of each party only what is profitable. On the one hand of the Jewish idea we have the unity of God's nature, and on the other, of the Greek, we have the distinction in subsistences and that only.

  But should the Jew refuse to accept the Word and the Spirit, let the divine Scripture confute him and curb his tongue. For concerning the Word, the divine David says, For ever, O Lord, Your Word is settled in heaven. And again, He sent His Word and healed them. But the word that is uttered is not sent, nor is it for ever settled. And concerning the Spirit, the same David says, You send forth Your Spirit, they are created. And again, By the word of the Lord were the heavens made: and all the host of them by the breath of His mouth. Job, too, says, The Spirit of God has made me, and the breath of the Almighty has given me life. Job 33:4 Now the Spirit which is sent and makes and establishes and conserves, is not mere breath that dissolves, any more than the mouth of God is a bodily member. For the conception of both must be such as harmonizes with the Divine nature.

In other words, John Damascus, writing long after the doctrine of Trinity was settled, said that the only element borrowed from paganism is the "distinction in subsistences", which to me is an Angle #3 activity (language refinement) to help describe the Trinitarian God.  The language borrowing doesn't add/remove God's attribute or add/remove the 3 persons (to make it 4 or 2, for instance).  Therefore, I don't think that counts as a pagan source of the dogma.  If we look at Chapter 1 title of the book it is quite obvious that the source is only OT and NT:

  "That the Deity is incomprehensible, and that we ought not to pry into and meddle with the things which have not been delivered to us by the holy Prophets, and Apostles, and Evangelists."

More resources:

PDF of Wolfson's book.  Your quote appears on page 362 (PDF page 401)
Reviews of Wolfson's book: here and here
Excellent Stanford Encyclopedia of Philosophy's History of Trinitarian Doctrines


How does a Christian justify free thinking?

Thinking is actually commendable and encouraged for Christians.

In Thessalonica, Paul's witness is recorded as follows:

And Paul went in, as was his custom, and on three Sabbath days he reasoned with them from the Scriptures, 3  explaining and proving that it was necessary for the Christ to suffer and to rise from the dead, and saying, “This Jesus, whom I proclaim to you, is the Christ.”  Acts 17:2-3

So, Paul's method was to reason and logically demonstrate the truthfulness of the Gospel.

After Thessalonica Paul traveled to Berea, who were commended by Luke as follows:

  Now these Jews were more noble than those in Thessalonica; they
  received the word with all eagerness, examining the Scriptures daily
  to see if these things were so.  Acts 17:11 ESV

The Bereans were commended for doing their research, considering what Paul was saying, and searching the Scriptures to verify the truthfulness of Paul's claims.  So, thinking was commended.

Throughout Scripture, God asks us to think, to consider, to contemplate.  Proverbs is full of exhortations to the many who makes wise decisions.  I have heard that the book of Romans apparently used to be used in Law Schools in America to demonstrate how to construct a logical argument.

Christianity proclaims itself as a logical, rational, convincing truth.  It invites the skeptic, the critic, and the scoffer to ponder.  Many of such people have done so and come to faith in Christ, notably Josh McDowell and Lee Strobel, among many others.


Under what conditions can one experience the power of the Holy Ghost?

Generally speaking, the "power of the Holy Ghost" is simply the manner in which He accomplishes His mission.  Again, generally speaking, LDS members don't distinguish a difference between the "power of the Holy Ghost" or any other of His duties or blessings.  So, let's explore a moment.

1) You mentioned the "Gifts of the Spirit" such as tongues, healing, prophecy, etc.  Certainly these occur through the power of the Holy Ghost, but they are an inexclusive application of that power.  Indeed, though personal unrighteousness may bury the gift or gifts, we believe that everyone has at least one gift of the Spirit, no matter who they are or what they believe (D&C 46:11).  Since this affects everyone and is conditioned only on personal righteousness, we'll set this aside as insufficient to answer your question.

Condition(s): Personal Righteousness

2) You mentioned the Gift of the Holy Ghost.  This isn't a specific power, but the ability (assuming once again personal righteousness) to have the Holy Ghost as a constant companion.  Let's start with Acts 2:38:

  Then Peter said unto them, Repent, and be baptized every one of you in
  the name of Jesus Christ for the remission of sins, and ye shall
  receive the gift of the Holy Ghost.

and end with D&C 20:26:

  ...but all those from the beginning, even as many as were before he
  came, who believed in the words of the holy prophets, who spake as
  they were inspired by the gift of the Holy Ghost....

From the LDS perspective, before Baptism and giving the formal Gift of the Holy Ghost people can be inspired by Him (He primarily acting in His role as testator), but they are not going to receive more from Him.  No revelations, no prophecy, no second comforter, no spirit of promise.  The goal of the Holy Ghost before Baptism is to lead people (a) to do good and (b) to Baptism.  Now, this technically answers your question about the Power of the Holy Ghost, but let's delve a bit more.

Condition(s): personal righteousness, baptism by proper authority

(Authority is a discussion all its own.  In our belief, Baptism can only be authoritatively performed by an ordained priest of the Aaronic Priesthood in the LDS Church or any member of the Melchizedek Priesthood.  We don't recognize any other baptisms.)

3) The Holy Ghost has specific roles.  The scriptures I list below are by no means exhaustive.

(a) A teacher, bringing all things to rememberance.  (John
14:26)
(b) A witness or testator (Acts 5:32)
(c) A motivator (Ezek 36:27)
(d) A conscience (Matt 12:18)
(e) A provider of revelation or visions (John 16:13)
(f) A sealer, the Holy Spirit of Promise (D&C 76:53-54 (132:7))
(g) And, a Servant of God, doing as God requires (Moses 6:64)

All these things are done with the Power of the Holy Ghost, but most won't happen consistently unless given the Gift of the Holy Ghost.

(a-e) Conditions: personal righteousness & authorized baptism.

(f) and (g) are specific issues and rare.

(f) The Holy Spirit of Promise (i) seals a person's calling and election sure (2 Pet 1:10) and (ii) seals a temple marriage for time and all eternity.  Both are required for the Celestial Kingdom and for our own families to persist forever.

(f.i) Conditions: exceptional personal righteousness, baptism, temple endowment.

(f.ii) Conditions: exceptional personal righteousness,  exceptional personal relationship with your spouse, baptism, temple marriage.

(g) is, perhaps, entirely unique.  One example was Adam's baptism, referenced above.  There are a handful of unique baptisms like his in scripture (another being Alma the elder).  In this role, the Holy Ghost is a unique "go-to" person to make a specific thing happen.  This is not an "achievable" condition.  You must be the right person, in the right place, at the right time, foreordained for the event.

Everything I have discussed happens by the "Power of the Holy Ghost," but I suspect that (3.f) is the most specific example of His unique power.

Please let me know if this addressed your question.  Thanks for giving me the chance to answer!


What is the Biblical argument used by Evangelical Christians against the Catholic doctrine of the invocation of the saints?

There are two main Protestant arguments against asking the deceased saints to intercede for us:

It is seen as contradicting the Bible's prohibition on contacting the dead. These are found most clearly in the Jewish Law, which is not binding on Christians, but is still considered to be solid wisdom in this case.

  Do not turn to mediums or seek out spiritists, for you will be defiled by them. I am the Lord your God. (Leviticus 19:31, NIV)

  Let no one be found among you who sacrifices their son or daughter in the fire, who practices divination or sorcery, interprets omens, engages in witchcraft, or casts spells, or who is a medium or spiritist or who consults the dead. (Deuteronomy 8:10-11)

It is thought that asking the saints to intercede for us is at best a waste of time, and at worst idolatrous, because Jesus is the best and perfect mediator, and no human can remotely compare to him. And while not all who do believe in the intercession of the saints think this way, there are many people who think that we are too sinful, too unworthy to directly approach Jesus in prayer, and for our requests to be heard we must go through Mary or the saints. Evangelical Protestants would consider this to be a gross distortion of the gospel.

  For there is one God and one mediator between God and mankind, the man Christ Jesus (2 Timothy 4:5)

  Now there have been many of those priests, since death prevented them from continuing in office; but because Jesus lives forever, he has a permanent priesthood. Therefore he is able to save completely those who come to God through him, because he always lives to intercede for them. (Hebrews 7:23-25)

This argument may not be very strong, because Protestants don't hesitate to ask living Christians to pray for them, but it's still an argument that gets made.
A third, more minor, argument is an argument from silence: this practice is not recognised as being taught or performed anywhere in the Bible.

This position ultimately arises from a different understanding of the Communion of Saints in Protestantism. Protestants would not deny the real union of living believers (the church militant) nor the union of believers who have passed away (the church triumphant), but they would generally not say that there is a functional union between those groups. We are united in our shared salvation state, our faith, our creed, our shared indwelling of the Spirit, our hope, and our inheritance, but we are not united with the dead in any relational capacity. There is much disagreement within Protestantism over the nature of the Intermediate State between death and resurrection, and many believe in soul sleep, that the dead are unconscious until the time of their resurrection. Others may believe that they are conscious, but that they do not have the means to hear our invocations and prayers.


What was Martin Luther's perspective on the early Christian church?

Luther, like other reformers, regarded the early church highly, but not above scripture.  We see this in two ways – (1) he accepted the earliest councils of the church as faithfully proclaiming the truth of scripture and (2) he respected many of the church fathers and benefited from their insights, though always judging them against scripture.
Councils
Manfred Schulze, in his article "Martin Luther and the Church Fathers," in The Reception of the Church Fathers in the West, I, helpfully reviews Luther's interaction with the fathers.  But he also describes Luther's acceptance of the first four ecumenical councils:

The four "principal Councils" of Nicaea, Constantinople, Ephesus and Chalcedon were (for Luther) all distinguished by the fact that they did not resolve on any new articles of faith, till then unheard-of, but provided genuine instruction from Scripture.  [...] The doctrinal pronouncements of the four principal Councils are really "Holy Scripture" for Luther, because they derived from genuine exegesis of Scripture by the Fathers of Councils. (590)

So it's clear then that Luther felt that in the essentials, the early church got off to a good start, since it faithfully taught the Bible in its first four Councils.
Fathers
Luther's respect for the church fathers is also clear, but again he places them under the authority of scripture.  Brian Litfin writes:

Martin Luther warmly embraced the church fathers whenever their comments dovetailed with scripture.  Luther's biblical commentaries are full of patristic citations.  He tells us he had thoroughly studied the fathers, and even endorsed the ideal of a reformation based upon their writings and the ancient creeds. (Getting to Know the Church Fathers, 27)

That said, Litfin makes Luther's selectivity clear in a footnote:

Luther's approach to the church fathers was always selective.  When he found them to be in harmony with scripture, he accepted them.  When he believed them to be contrary to scripture, he felt the freedom to reject them on that point. (270)

One way Luther compared the relative authority of the Bible and the fathers is by adopting the analogy of St. Bernard, in On the Councils and the Church (1539):

He [St. Bernard] admits that he held the holy fathers in high esteem, but was not by any means an entire convert to their opinions.  He assigns the following cause, and draws this comparison, viz., that he would prefer to drink from the fountain at once than from the streamlet. [...] Thus must the Scriptures hold the rank of master and judge, otherwise should we have too much recourse to the brooks [the church fathers]. (22–23)

Based on all this, we'd expect that Luther appreciated some fathers more than others.  And that is indeed the case.  Perhaps foremost among them was Augustine, who paved the way for Luther's views on sin, but (according to Luther) still didn't fully understand Paul.  Luther also thought that even the doctrine of justification by faith alone could be found in several fathers, though he wished it appeared more clearly.  Manfred Schulze writes:

At the beginning of his great lecture on Genesis Luther reports that because he knew of justification by faith from Scripture he also found it in Augustine, Hilary, Cyril and Ambrose, even if they did not zealously pursue it in practice and at time talked about it only inappropriately.  "But I don't count that as an error on their part" is his conciliatory comment; "it suffices if they say the same thing on the subject; even if they scarcely express it appropriately, their testimony bears me out". (612)

Schulze's article mentions other fathers toward whom Luther was less generous, like Pope Gregory, who "produced nothing good with his teaching" (612), Jerome "does not know what the gospel is and does not understand what the law amounts to" (609), and Origen and Cyprian, neither of whom "preached Christ" (615).  Schulze concludes that the fathers were merely "theological controversialists" for Luther, "no less, but also no more":

Church Fathers are criticized, but are also praised for having assembled much that was correct, e.g. on the Psalter, even if at times their expositions of the meaning of the text diverge widely.  The same as happens to all exegetes is the fate of the Fathers too in their exposition of Scripture—"One makes a mistake here, another there." (615)

Conclusion
Luther certainly believed that there was much of value in the early church – the first four councils, and many of the writings of the fathers.  So it is fair to say that he saw his work as a reform, and not a completely new beginning.  But at the same time, he did not regard those in the early church as authoritative – ultimately he judged everything against the singular authority of the Bible.


What kind of characteristics does the Great Tribulation have in LDS eschatology?

Before I begin I'd like to restate from the other answer that the phrase "Great Tribulation" is not used in Mormon terminology/teachings and LDS teachings most closely align with post-tribulationist. That is Mormon's believe in a chronology that is along the lines of tribulation, second coming, Millenium, and then the last judgement. I will not go into great detail as most of this is covered in LDS manuals and covers several chapters, feel free to look at the referenced manuals if you want more detail.

  What physical events do Mormons believe will happen before or during the Great Tribulation?

Signs of the Second coming1

Wickedness, War, and Turmoil-being fulfilled
The Restoration of the Gospel-fulfilled
The Coming Forth of the Book of Mormon-fulfilled
The Gospel Preached to All the World-partly being fulfilled
The Coming of Elijah-fulfilled
Lehi's Descendants Will Become a Great People-partly being fulfilled
Building of the New Jerusalem
Other signs (see the scripture references at the bottom of the chapter if you want the others)

Second Coming2

Jesus will cleanse the earth-wicked will be destroyed
He will judge His people
He will usher in the Millenium
He will complete the First Resurrection
He will take His rightful place as King of heaven and earth

Millenium3

Temple/Missionary work
Satan bound
Peace on earth
Righteous government
No death
All things revealed
A final struggle at the end of Millenium when Satan will be set free for a short time. Satan will gather his armies and they will be cast out forever.

Final Judgement4

Judged by words, works, and thoughts
Judged by records
Inheriting a place in a Kingdom of Glory

  In what sense will it be a "Great Tribulation" - is this mostly symbolic or are there spiritual or physical (e.g. economical) reasons that warrant the label "Great Tribulation"?

Because this isn't Mormon terminology it is hard to get a specific answer but based on the previous answer (above) there are spiritual and physical reasons that would warrant the label "Great Tribulation".

  Do Mormons have any official beliefs on how long the Great Tribulation is expected to last?

No. We have to measure when the first sign of the Jesus' Second Coming is to the Second coming (no specific time period), plus 1,000 year Millenium, and then Final Judgement (again no specific time period). So at least 1,000 years.

1 https://www.lds.org/manual/gospel-principles/chapter-43-signs-of-the-second-coming?lang=eng

2 https://www.lds.org/manual/gospel-principles/chapter-44-the-second-coming-of-jesus-christ?lang=eng

3 https://www.lds.org/manual/gospel-principles/chapter-45-the-millennium?lang=eng

4 https://www.lds.org/manual/gospel-principles/chapter-46-the-final-judgment?lang=eng


When did "he descended into hell" become part of the Apostles' Creed?

For the larger context of the authorship and development of the creed, please see my answer to this question: Did the Apostles' Creed originate with the Apostles?

Church historian Philip Schaff provides a summary of the development of the Apostles' Creed in his book, The Creeds of Christendom.  A helpful table, showing the creed's gradual formation in the West from AD 200 to 750, can't be reproduced in full here, but I'll quote the relevant part, listing each version of the creed, the year, and the wording of the "descent into hell" clause, if included:1

         Version                Year           Clause?
   St. Irenaeus                AD 200            --
   Tertullian                  AD 220            --
   St. Cyprian                 AD 250            --
   Novatian                    AD 260            --
   Marcellus                   AD 341            --
   Rufinus (Alquileja)         AD 390     DESCENDIT in INFERNA
   Rufinus (Rome)              AD 390            --
   St. Augustine               AD 400            --
   St. Nicetas                 AD 450            --
   Eusebius Gallus             AD 550            --
   Sacramentarius Gallicanum   AD 650     Descendit AD Inferna
   Pirminius (current)         AD 750     Descendit ad Inferna

It's not clear from my table, but if you look at the original, which shows all the clauses of the creed for each of these versions, you'll notice that this particular clause is one of the least-attributed of all of them.  Especially notable is that it only appears in one version of the creed before AD 600.2

With respect to the first orthodox version containing the phrase (AD 390), Scaff notes that Rufinus didn't actually interpret the phrase in the Alquileja version the normal way: he thought it meant the same thing as the previous clause, "buried."3  If that's the case, then the first intentional orthodox/Western use of "descent into hell" was in AD 650.

This history has encouraged some to call for removing the clause from the creed, such as Protestant theologian Wayne Grudem.4  Grudem and others, like John Piper,5 also dispute the clause with biblical arguments, so it's likely that Protestant churches that have removed the clause from their creeds are doing so only partially because of the clause's history.

References and notes:

Schaff, Creeds of Christendom, Volume 2, p54 (Also on Google Books).
Schaff does not include in this list the versions produced by the Arians (Eastern heretics), but does briefly mention that Arian versions from AD 360 and AD 590 include the clause. (see following citation)
Schaff, Creeds of Christendom, Volume 2, p46n2 and Volume 1, p21n4.
Grudem, "He Did Not Descend Into Hell." JETS vol. 34, no. 1, p103-13; also available in his Systematic Theology (582-594).
Piper, "Did Christ Ever Descend to Hell?" Interview, 2008-03-03.


Is the Christian concept of the Trinity influenced by Philo's philosophy?

Answer

Original question: Was the Christian concept of the trinity inspired by Philo's philosophy?

No, the Christian concept of the Trinity is not inspired by Philo's philosophy. It seems most probable that Philo based some of his writings on the Trinity from his knowledge of Jesus and Holy Spirit in the events of the Gospels, some writings as a philosophical expansion on the previous renderings of the Logos, and some writings based on the Old Testament, as the word Logos in the Septuagint appears quite often. See this link. Additionally, you asked

  How can it be shown that Christian theology was not influenced by Philo's philosophy?

"Influenced by" is quite distinct that "inspired by," unless you meant these words to be synonymous. "Inspired by" generally entails being the source of something, vs an "influence" just affects something else in any way, shape, form, or extent. I would say that Christian theology is/was influenced by Philo, probably even a much smaller extent compared to Arian. So the exact answer would be I don't think it can be shown, because it seems probable that Christian theology was influenced by Philo, though not inspired by.

Discussion

The exact answer to your question depends on what exactly you mean by the "Christian concept of the Trinity." If you are referring to the creeds formulated at Nicaea, then it is probable that those were affected by Philo's heterodox teachings. If you are referring to the doctrine of the Trinity as believed by ante-Nicene church fathers, then it is also probable that Philo's writings affected them, since ante-Nicene includes all of 1st century up until 325 AD. If you are referring to the doctrine of the Trinity itself, then no...see below.

An important element of this question hinges on the dating of Philo's works, since he lived 20 BC to AD 50. If the Christian concept of the Trinity is inspired by Philo's writings, then his relevant writings should be prior to when the Christian concept of the Trinity was established. I have unsuccessfully attempted to find any date given to Philo's writings, of which the ones including the Trinity and the Logos being the most relevant and central to this question. Philo spent a large portion of his writings and his life on Genesis and the Pentateuch rather than the Trinity.

The concept of the logos is familiar to Greek philosophy prior to Jesus' time and starting in the 5th century BC with Heraclitus, though with somewhat of an inconsistent and transient usage. Aristotle used logos in combination with ethos and pathos in his writings on persuasion. Read more here. Philo's discussion of the Logos could be a purely philosophically-based expansion on the previous philosophical/theological renderings of Logos, as the Logos had already had theological implications at least with the Stoics in the 4th century BC.

The New Testament writings were most likely all written after the death of Philo in AD 50; however, the events of the Gospels all happened by AD 30.  The earliest church father I am aware of besides the New Testament writers, Ignatius of Antioch, was born in AD 35. I doubt he would have been able to write a treatise on Jesus as the Logos before Philo did. I don't know if we can know how the apostles applied the term Logos to Jesus before the Gospel accounts. In Eusebius' Ecclesiastical History, Peter and Philo supposedly met, which is relevant. It is also possible that Philo was familiar with the events occurring with Jesus, including the Holy Spirit, Pentecost, "breathing" the Holy Spirit on the disciples, etc., which explains some of Philo's writings on the Holy Spirit (pneumatology) and the Trinity. He probably (possibly?) would have been familiar with what the Christians taught and believed about Jesus, so that most likely would have affected his writings.

You could prove me false by demonstrating that Philo's writings on the Trinity pre-date the events of the Gospels (before ~AD 25). It is difficult to otherwise separate what Philo knew of Christian beliefs at the time of his writings. Jesus was born around 4-6 BC, so his ministry started around AD ~25-27, so if Philo wrote extensively on the Trinity (especially and specifically pneumatology) before the events described in the Gospels, then I would be wrong. Otherwise, I would think it is the Gospel events (not the books) that are Philo's primary basis for his doctrine.  To have such sophisticated work on the Trinity would be extremely surprising based on the Old Testament alone.

Conclusion

In short, this is a great and difficult question; I don't think we have the data to come to a solid conclusion on this. And this was a terrible answer but just wanted to give you some information for your consideration in finding an answer to this question. Summary: I think Philo based his writings on the Logos from the Old Testament and philosophy, but his writings on pneumatology the events contained in the Gospels that he would have heard about.

Edit: This link (also linked in the Answer section) helped me see you could have some substantive writings on the Logos from the Old Testament alone, especially with a philosophical background because Logos appears a decent amount in the Septuagint, the Greek translation of the Hebrew Scriptures (Old Testament).

Therefore, it seems that Philo bases his ideas of the Logos on philosophy + Old Testament considering that he does quote it, see this answer, but the ideas of pneumatology on Gospel events since those seem to be very specifically from Jesus' ministry and teachings, and probably some overlap between the two. Jesus often referred to the Old Testament to reveal the Trinity, so Philo could have been aware of that.

P.S. if someone can give me dates for any/all of Philo's writings, that would be wonderful.


In protestantism are all mankind equal under God?

There are over 900 million Protestants worldwide.  The largest Protestant denomination seems to be Anglicanism with 85 million members, followed by Baptist, Lutheranism, Methodism and Calvinism.  Another consideration is the denominations that make up “Modern Protestantism” – 400 to 500 million. Then we have non-denominational / evangelical Protestants – 80 to 100 million.  And then there are the 35 million members of non-Trinitarian denominations.  Source: https://en.wikipedia.org/wiki/List_of_Christian_denominations_by_number_of_members#Protestantism_%E2%80%93_920_million

Asking what are the views “in Protestantism” about equality, worth and respect, is therefore problematic because some denominations may subscribe to more liberal views than others.  To find out what one specific denomination believes, you would need to examine their official Statement of Faith and drill down to find what each has to say on the topics you mention.  However, it is possible to take a biblical overview – a generalisation – in order to establish what Bible-believing Protestant denominations should adhere to.  As a Christian of the Reformed Protestant persuasion here is my response to your questions:

Yes, Protestants understand that we are all equal under God.  It doesn’t matter if you are a King or a Queen, a President or a pauper.   The basis of equality has to do with how God views us.  God is holy, righteous and just and the sad truth is that every person is born with a sin nature.  The hard truth is that we have all sinned (Romans 5:12) and if we claim to be without sin we have deceived ourselves (1 John 1:8).  In that sense, we are all equal under God.

However, I suspect what you are really asking is how Protestants view other people.  Do they see everyone else as being equal?  Do they think some people are of higher worth than other people?  Do they believe that everyone deserves equal respect?

Do Protestants see everyone else as being equal?  Yes, whilst understanding that no created being can ever be equal to God (Isaiah 40:25).

Do Protestants think some people are of higher worth than other people?  No.  On the contrary, according to Philippians 2:3, we should “do nothing out of selfish ambition or vain conceit, but in humility consider others better than ourselves”.

Do Protestants believe that everyone deserves equal respect?  Christians are told to show proper respect to everyone (1 Peter 2:17).  That includes showing respect within the family, to employers, to government officials, to rulers.  Those are people who deserve respect.

Ultimately, the bottom line is that it is God alone who is worthy of our respect (Malachi 1:6) and Protestants seek to follow the example of Christ Jesus in their dealings with other people.

Edit in response to clarification from OP: Jesus said the most important command is to love the Lord our God with all our heart, soul and mind.  The next, like it, is to love our neighbour as we love ourselves (Matthew 22:37-39).  That means our actions are to be motivated by our love of God and our love of others.  If we say we love God then we are bound to show Christ-like love for other people, regardless of their age, race, gender, origin of birth, skin colour, or state of health.

We should respect all people, remembering that we are all created in God’s image, regardless of our religious beliefs (or non-belief).  Take the example of the “Good Samaritan” in Luke 10:33-34, who went to extraordinary lengths to help the Jewish victim of robbers, even though the Samaritan himself was despised by the Jews.

Christians are advised to follow the example of the Apostle Paul who said:

  I try to please everybody in every way for I am not seeking my own good but the good of many, so that they may be saved.  Follow my example, as I follow the example of Christ. (1 Corinthians 10:33)

If we claim to be followers of Christ Jesus then we are bound to walk in his footsteps, to show compassion to the lost, the dispossessed, widows and orphans, to visit the sick and to care for those in need.  There is no room for discrimination.


In Romans 7 is Paul talking about before or after he was saved?

The passage was written after his conversion, and there is no indication whatsoever that Paul was speaking in the past tense.  Therefore, following the basic rules of interpretation, (particularly #3, 5, and 8) he is speaking about after he was saved.

Those eight rules are copied from the Apologetics Research page below:

  1 The rule of DEFINITION: What does the word mean? Any study of
  Scripture must begin with a study of words. Define your terms and then
  keep to the terms defined. The interpreter should conscientiously
  abide by the plain meaning of the words. This quite often may require
  using a Hebrew/English or Greek/English lexicon in order to make sure
  that the sense of the English translation is understood. A couple of
  good examples of this are the Greek words "allos" and "heteros". Both
  are usually translated as "another" in English - yet "allos" literally
  means "another of the same type" and "heteros" means "another of a
  different type."

  2 The rule of USAGE: It must be remembered that the Old Testament was
  written originally by, to and for Jews. The words and idioms must have
  been intelligible to them - just as the words of Christ when talking
  to them must have been. The majority of the New Testament likewise was
  written in a milieu of Greco-Roman (and to a lesser extent Jewish)
  culture and it is important to not impose our modern usage into our
  interpretation. It is not worth much to interpret a great many phrases
  and histories if one's interpretations are shaded by pre-conceived
  notions and cultural biases, thereby rendering an inaccurate and
  ineffectual lesson.

  3 The rule of CONTEXT: The meaning must be gathered from the context.
  Every word you read must be understood in the light of the words that
  come before and after it. Many passages will not be understood at all,
  or understood incorrectly, without the help afforded by the context. A
  good example of this is the Mormon practice of using 1 Cor. 8:5b:
  "...for there be gods many and lords many..." as a "proof text" of
  their doctrine of polytheism. However, a simple reading of the whole
  verse in the context of the whole chapter (e.g. where Paul calls these
  gods "so-called"), plainly demonstrates that Paul is not teaching
  polytheism.

  4 The rule of HISTORICAL BACKGROUND: The interpreter must have some
  awareness of the life and society of the times in which the Scripture
  was written. The spiritual principle will be timeless but often can't
  be properly appreciated without some knowledge of the background. If
  the interpreter can have in his mind what the writer had in his mind
  when he wrote - without adding any excess baggage from the
  interpreter's own culture or society - then the true thought of the
  Scripture can be captured resulting in an accurate interpretation.
  Oliver Wendell Holmes said, "Our only interest in the past is for the
  light it throws upon the present."

  5 The rule of LOGIC: Interpretation is merely logical reasoning. When
  interpreting Scripture, the use of reason is everywhere to be assumed.
  Does the interpretation make sense? The Bible was given to us in the
  form of human language and therefore appeals to human reason - it
  invites investigation. It is to be interpreted as we would any other
  volume: applying the laws of language and grammatical analysis. As
  Bernard Ramm said:

  "What is the control we use to weed out false theological speculation? Certainly the control is logic and evidence...
  interpreters who have not had the sharpening experience of logic...may
  have improper notions of implication and evidence. Too frequently such
  a person uses a basis of appeal that is a notorious violation of the
  laws of logic and evidence." (Protestant Biblical Interpretation,
  Boston: W. A. Wilde, 1956)

  6 The rule of PRECEDENT: We must not violate the known usage of a
  word and invent another for which there is no precedent. Just as a
  judge's chief occupation is the study of previous cases, so must the
  interpreter use precedents in order to determine whether they really
  support an alleged doctrine. Consider the Bereans in Acts 17:10-12 who
  were called "noble" because they searched the Scriptures to determine
  if what Paul taught them was true.

  7 The rule of UNITY: The parts of Scripture being interpreted must be
  construed with reference to the significance of the whole. An
  interpretation must be consistent with the rest of Scripture. An
  excellent example of this is the doctrine of the Trinity. No single
  passage teaches it, but it is consistent with the teaching of the
  whole of Scripture (e.g. the Father, Jesus, and the Holy Spirit are
  referred to individually as God; yet the Scriptures elsewhere teach
  there is only one God).

  8 The rule of INFERENCE: An inference is a fact reasonably implied
  from another fact. It is a logical consequence. It derives a
  conclusion from a given fact or premise. It is the deduction of one
  proposition from another proposition. Such inferential facts or
  propositions are sufficiently binding when their truth is established
  by competent and satisfactory evidence. Competent evidence means such
  evidence as the nature of the thing to be proved admits. Satisfactory
  evidence means that amount of proof which would ordinarily satisfy an
  unprejudiced mind beyond a reasonable doubt. Jesus used this rule when
  he proved the resurrection of the dead to the unbelieving Sadducees in
  Matt. 22:23-33.

  Learning these eight rules and properly applying them will help keep
  any interpreter from making errors and will hopefully alleviate many
  of the disagreements unfortunately present in Christianity today.
  However, these eight principles are no substitute for the Holy Spirit
  which will, if you let Him, guide you in the truth [John 14:26]. If
  you receive Christ into your heart, God will give you the Holy Spirit
  freely as a gift [Acts 2:38]. I urge you, if you have not already done
  so, to examine the claims and the work of Jesus Christ and to receive
  Him as your Savior.

To come to the conclusion that he is speaking of only before he was saved, you'd have to ignore verb tense and other basic rules of interpretation.


How can one offer Christ's sacrifice to God?

Part of the answer can be found in Colossians 1:24.

  Now I rejoice in my sufferings for your sake, and in my flesh I complete what is lacking in Christ's afflictions for the sake of his body, that is, the Church.

The question a Christian must answer is, "What is lacking in Christ's afflictions?"  I think most would agree that nothing at all is lacking, so what does Paul mean?

From a Catholic worldview, when we are baptized into Christ, we are part of the body of Christ.  Being part of that body is not simply metaphorical but actual and real.  Saint Bridget has made Christ's sacrifice her own by uniting herself to that sacrifice in her devotions and selfless life, forming herself ever more into the likeness of Christ.

God the Father is well aware of Christ's sufferings, as his mother is and as we should be. We are called as Catholics to unite our sufferings to Christ's.

Bridget in her prayer is acknowledging Christ's sacrifice and joining herself to it, like Paul suffering for Christ's sake for the Gospel to our benefit. In this prayer, she points out the blood that the Lord sweat from his skin in the garden.

By combining this prayer with the Hail Mary and Our Father, Bridget shows this prayer to be contemplative prayer, like the rosary.  In contemplative prayer, she prays not just by repeating the verses, but rather by putting herself in the garden in the anticipation and fear that the Lord experienced. By imagining herself as Jesus and experiencing the fear and pain of what is coming, including the falling away by the few that should have been faithful, she joins in that suffering. Contemplative prayer is a powerful way to unite to Christ and experience his suffering.

In your question you asked:

  I don't fully understand how can one offer somebody's else suffering to gain grace for oneself.

Bridget is not offering just anybody's suffering up to the Lord, only the suffering of the one person whose suffering can and does merit grace.


Why are some of the Psalms written by authors other than David?

Psalms is a collection of songs written by many people, compiled latter by some unknown editor. Though David wrote many songs, he did not write all the songs. Some songs were written before David and some after him.

  The Psalms were written by numerous people over 1,000 years of
  Israel 's history. Some of the Psalms were written as far back as the
  time of Moses in 1500 BC. Others were written as late as the time of
  Ezra around 500 BC. Most, however, were written in the time of King
  David. David himself wrote more of the Psalms than any other author,
  composing 73 songs in this collection. While modern scholars often
  express doubts as to David's authorship, the bible affirms that the
  king was an accomplished musician (1 Samuel 16:18) who was also a
  great patron of the temple music (1 Chronicles). He is titled in 2
  Samuel 23:1 as the sweet psalmist of Israel .

  The Psalms were collected and compiled at various times throughout
  Israel 's history. Various collections and books of Psalms were
  gathered together and published as song books and hymnals. There is
  evidence of heavy editing of the Psalms. For example, Psalm 14 is
  almost identical to Psalm 53, except in Psalm 14 the name Yahweh is
  used for God, while in Psalm 53, the name Elohim is used. Psalm 108 is
  a medley of Psalm 57 and Psalm 60, put together for a new occasion.

  Therefore, the final order and arrangement of the Psalms suggests a
  single editor who brought ancient collections and songs together
  into the final form. The final form of the Psalms is arranged into
  five books.

  There are some scholars who connect the five books of the Psalms with
  the five books of the Torah. Most of these connections, however,
  stretch the connection beyond what is reasonable.

  SOURCE

The date of compilation is unknown. Some suggest it to be about 537 B.C. and some believe it to be around the Third Century B.C.


Why did Martin Luther change his surname from ‘Luder’ to ‘Luther' very early in his career?

According to a book by James Nestingen,

  On Luther's "Gospel discovery," his "tower experience," I agree with Nestingen (and Lohse) that it probably coincided with his name change from Luder the Luther, "a small change based on the Greek word for freedom, elutherius. I see the similarity as too exceptional simply to explain Luther's name change as merely a respelling from Low/Middle German to High German.

http://www.amazon.com/Martin-Luther-James-A-Nestingen/dp/0800697146

The reason for choosing a word related to "freedom" has to do with the freedom offered by the Gospel.