Are Catholics prohibited from getting their body tattooed?
There is no official Catholic condemnation against getting tattoos. I know some priests who have tattoos! The whole idea of getting tattoos is to say the least very discouraged by the Church.
If the Church forbids us from mutilating our bodies, does this mean that getting a tattoo is against the teachings of the Catholic Church?

First of all, the Church has not made any kind of formal decision on the matter of tattoos. There is some Biblical evidence on this, for example, a passage in Leviticus that says:
"You shall not make any cuttings in your flesh on account of the dead or tattoo any marks upon you: I am the Lord" (Lev. 19:28).
Yet, it seems that this prohibition was present so as to avoid the people of Israel from following the pagan mourning practices of the Canannites. Moreover, these Old Testament ritualistic laws are not binding on Christians.
The Church does say that we should avoid practices that mutilate or damage our body, as you can see in no. 2296 of the Catechism.

The question of tattoos was on the mind of at least one pope. Pope Hadrian I forbade the usage of tattoos on one's body in 787 AD.

In 787 AD, Pope Hadrian banned tattooing. It still thrived in Britain until the Norman Invasion of 1066. The Normans disdained tattooing. It disappeared from Western culture from the 12th to the 16th centuries. - A Brief History of Tattoos

Nevertheless there were a few exception from this ban of tattoos by Pope Hadrian I.

Christian tattooing rarely enters the written record but when it does, it does so in interesting ways. Pope Hadrian I, in 787 AD, banned tattooing (since it was associated with heathen practices) but there was an exemption for religious tattoos since they would “bring spiritual rewards.”
In the Medieval period, mentions of tattoos become more numerous including clerics (such as Dominican priest and German mystic Heinrich Suso (1295-1366) who tattooed the name of Jesus over his heart). - Christian Tattooing

Why did British sailors get the Crucifixion scene tattoo on their backs.

European sailors were known to tattoo the crucifixion on their backs to prevent flogging (since it was a crime to deface an image of Christ). - A Brief History of Tattoos

Here is a sample of a genuinely Catholic tattoo from Seven Types of Christian Tattoos.
I also know of some World War II marines (Catholics and non-Catholics alike) who got their dog tag numbers tattooed to their torsos or major portions of their limbs, for identification reasons in combat situations.

Why two dog tags are issued to soldiers?]9 The dog tag tattoo makes a third and permanent dog tag and often indicates the religious affiliations of soldiers.

Dog tag is an informal but common term for a specific type of identification tag worn by military personnel. The tags' primary use is for the identification of casualties; as such, they have information about the personnel written on them, and convey essential basic medical information such as their blood type and history of inoculations. They often indicate religious preference as well.
A pair of blank dog tags on a ball chain
Dog tags are usually fabricated from a corrosion-resistant metal. They commonly contain two copies of the information, either in the form of a single tag that can be broken in half, or as two identical tags on the same chain. This purposeful duplication allows one tag, or half-tag, to be collected from a personnel's dead body for notification, while the duplicate remains with the corpse if the conditions of battle prevent it from being immediately recovered. The term arose and became popular because of the tags' resemblance to animal registration tags.


What happened to Nebuchadnezzar's kingdom during his punishment

Daniel 4:29-33 is the culmination of writings, beginning with a Babylonian history, a series of Dead Sea Scroll fragments known as pseudo-Daniel and then the biblical book of Daniel.

M. H. Henze (The Madness of King Nebuchadnezzar, pages 57ff) identifies King Nabodinus (556-539) as the last king of Babylon, although his name never appears in the Hebrew Bible. His history was put together from a number of Babylonian cylinders discovered in 1854 at Tell al-Muqayyar (Ur). One of the cylinders names the king's son as Bel-sarra-usur, who was quickly identified as Belshazzar, given in Daniel as the son of Nebuchadnezzar. Thus it was possible to identify Nabodinus of the Babylonian texts with Nebuchadnezzar of the Book of Daniel.

The Babylonian texts tell us that Nabodinus left Babylon for ten years, to sojourn in Teima in the Arabian Peninsula, where he spent his time in devotion to the moon god, Sin, while his son Belshazzar ruled as regent in Babylon. On page 63, Henze says that according to a wide consensus, the story of Nebuchadnezzar's madness contains a recollection, however distorted, of Nabodinus' self-imposed exile at Teima.

The discovery of the Dead Sea Scrolls between 1946 and 1956 confirmed a link between the Babylonian writings and Daniel chapter 4. One Scroll fragment, known as 4Q The Prayer of Nabonidus closely resembles the account we see in Daniel 4:29-33.

Craig A. Evans, Peter W. Flint (Eschatology, Messianism, and the Dead Sea Scrolls, page 58) say the Aramaic Prayer of Nabonidus mentions Nabonidus and Teima, while agreeing with Daniel in giving the length of the sojourn as seven years. It describes the king as having a bad disease and attributes his recovery to a Jewish exile, without mentioning anyone called Daniel. Evans and Flint say we may conclude that 4QPrNab occupies an intermediate place between the Babylonian accounts of a historical incident and the formation of the Book of Daniel.

We know from the Babylonian histories that the kingdom continued during the absence of Nabonidus (Nebuchadnezzar), with his son, Belshazzar, acting as regent.


What is the Orthodox teaching about touching Jesus' body?

Jesus didn't want Mary (and others) touching him as they had before the crucifixion, because he would no longer be with them as he had been. John Chrysostom explains this in his Homilies on the Gospel of St. John. [emphasis mine]

  Some assert, that she asked for spiritual grace, because she had heard Him when with the disciples say, “If I go to the Father, ‘I will ask Him, and He shall give you another Comforter.’” But how could she who was not present with the disciples have heard this? Besides, such an imagination is far from the meaning here. And how should she ask, when He had not yet gone to the Father? What then is the sense? Methinks that she wished still to converse with Him as before, and that in her joy she perceived nothing great in Him, although He had become far more excellent in the Flesh.

  To lead her therefore from this idea, and that she might speak to Him with much awe, (for neither with the disciples doth He henceforth appear so familiar as before,) He raiseth her thoughts, that she should give more reverent heed to Him. To have said, “Approach Me not as ye did before, for matters are not in the same state, nor shall I henceforth be with you in the same way,” would have been harsh and high-sounding; but the saying, “I am not yet ascended to the Father,” though not painful to hear, was the saying of One declaring the same thing.

  For by saying, “I am not yet ascended,” He showeth that He hasteth and presseth thither; and that it was not meet that One about to depart thither, and no longer to converse with men, should be looked on with the same feelings as before. And the sequel shows that this is the case.
  “Go and say unto the brethren, that I go unto My Father, and your Father, unto My God and your God.”

With Thomas it was another matter. When Jesus let Thomas touch him, it was a form of rebuke for Thomas' disbelief. Chrysostom again:

  Jesus again presenteth himself to them, and waiteth not to be requested by Thomas, nor to hear any such thing, but before he had spoken, Himself prevented him, and fulfilled his desire; showing that even when he spake those words to the disciples, He was present. For He used the same words, and in a manner conveying a sharp rebuke, and instruction for the future.

  For having said,
  “Reach hither thy finger, and behold My hands; and reach hither thy hand, and thrust it into My side”; He added,
  “And be not faithless, but believing.” Seest thou that his doubt proceeded from unbelief? But it was before he had received the Spirit; after that, it was no longer so, but, for the future, they were perfected.

  And not in this way only did Jesus rebuke him, but also by what follows; for when he, being fully satisfied, breathed again, and cried aloud,
   “My Lord, and my God,” He saith,
   “Because thou hast seen Me, thou hast believed; blessed are they who have not seen, and yet have believed.”


Is it right for us to help more non-Christians people as compare to Christians? jesus sacrifice for us then more eligible christians or some ane else?

You should help people despite them being Christian or non-Christian

Mark 12:31 NIV

  The second is this: 'Love your neighbor as yourself.' There is no
  commandment greater than these.

What is important is that it does NOT say, "love your neighbor as yourself, if he believes like you do".  Also, I would suggest that it would be against Jesus' teachings to even consider helping someone or not based on their status of being a Christian, Jew, or neither.

There's another way to read the OP's question, which would be, "why isn't American (being a Christian nation) helping Christians in Pakistan?"  If that is the OP's intended question, then the question is political and off topic for Christianity.SE.  Christians in Pakistan (or any other country) shouldn't expect America to specifically help them due to their Christian status.  America is not a Christian nation and is not the leading voice for Christianity.  76% of people in America identify themselves as Christian.  Christians generally assert that America was founded on Christian principles and many would assume (but not say) that it is a Christian nation.  However, it's just as likely that America has influenced Christianity.  For example, toleration of other faiths is not a Christian principle - especially during the dark ages.  Does that appear to contradict the above bible quote?  Yes, yes it does.  Therefore there are differences between the mainstream Christian Church and some teachings from the bible for better or worse.  There are too many to list here and I will not engage in a comment tit for tat with anyone over this.


What fancy word describing a church's stance on the Eucharist most closely applies to Mormonism?

In the The Church of Jesus Christ of Latter-day Saints the Eucharist is generally called "the Sacrament." Though priesthood authority is required to administer it, there is no concept of transubstantiation or cosubstantiation. The act of taking the bread and water is a token of rememberance of Christ and a renewal of baptismal and other covenants necessary for repentance.

More information about the Sacrament can be found here


Did the pool of Bethesda have healing powers?

I don't believe there is such a thing as a "perfect" translation of scripture, but there is an interesting thing to note about the verse you mention. One of the English translations I personally trust the most is the ESV. If you try to look this verse up in an ESV Bible you will find that it skips from verse 3 to 5.

Wait, what!?!

According to their footnote and the Study Bible commentary there is a significant problem with the manuscripts for this passage in that the phrase in question is not found in the earliest known manuscripts. The translators made the following judgement call:

  The statement in the ESV footnote about an angel of the Lord stirring the water and the first person who stepped in being healed is found in some early manuscripts, but not the earliest. Therefore the omitted verse 4 should not be considered part of Scripture, although v.7 (which is in all manuscripts) shows that people believed something like what this statement reports.

I do not know much about this particular passage of scripture, but I think it's reasonable to interpret the whole business with the pool to be a folk tradition rather than a valid source of magic healing. I do not know of any recorded evidence of specific/significant/verifiable miracles stemming from the pool, although I don't know that we can rule out the possibility just on principle.

I believe it is important to note that in all cases of healing, the healing stems from God and the focus of our attention should always be on Him rather than whaver medium He chose to use to reveal that healing. One example of this can be seen here:

  Matthew 9:20-22 (ESV)
  20 And behold, a woman who had suffered from a discharge of blood for twelve years came up behind him and touched the fringe of his garment, 21 for she said to herself, “If I only touch his garment, I will be made well.” 22 Jesus turned, and seeing her he said, “Take heart, daughter; your faith has made you well.” And instantly1 the woman was made well.

I think the important thing to note about this passage is that it was not Jesus garment that provided healing, but Jesus power to heal that He chose to bestow upon the woman on account of her faith in Him (not in His garment).


Does any church still provide a pension for widows?

Let's start by remembering that we are living in very different times from those of the New Testament. 1 Timothy is a letter written by one pastor to another, and not all of it is intended as commandments to the entire church in all places down the millenia. Some of it is Paul giving Timothy good advice for the present circumstances (Sometimes we can deduce universal principles from that, but that's a different matter). So asking whether any church is  ministering to widows in the way specified should be a trivial and unimportant matter, and doesn't in any way make a statement about the church. You should also consider that nothing in 1 Timothy says that widows under the age of sixty shouldn't receive help in other ways if they need it. Let's also remember that providing financial assistance to the elderly is now the responsibility of the state, at least in the Western world.
Having said that, many churches provide financial assistance specifically aimed at Widows. Here are a couple of examples:

The Widows Program of the Rafiki Foundation gives African widows and impoverished women of the church a means of employment and artistic expression
The orphan and the widow are often forgotten, marginalized and in need. God longs to meet their needs through us, His Church. Africa Revolution is being used by God, not only to help meet these needs, but also to equip and empower local churches and community members to better serve this population with best practice solutions.
Widow Connection - Helping Widows in time of need.
The mission of the Women Of Grace Widows’ Fund is to enact and make real an ongoing structure to alleviate the extreme poverty faced by widows in Malawi by providing funding to meet basic food, shelter, and safety needs, while creating opportunities and resources that enable and empower widows to establish their own self-sufficiency and independence, regardless of religious affiliation.

That's just from the first two pages of Google.


How should Christians participate in a democracy?

If we believed that Christianity was merely a good way to live, then there might be a justification for simply adhering to a "live and let live" philosophy such as it pertains to society and social issues.  But it's not; rather Christianity is the expression of God's plan of salvation for a fallen creation, and our moral code is the expression of God's perfect and absolute moral law.
As Christians, we are called to be the "salt of the earth" and the "light of the world":

Matthew 5:13-16
13 “You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot.
14 “You are the light of the world. A town built on a hill cannot be hidden. 15 Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. 16 In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven.

Salt is a natural preservative, slowing down the spoiling of food - it's not about changing the taste of the food it's about inhibiting the speed at which it rots.  Additionally, a light dispels darkness - where there is light, darkness ceases to reign and dominate.
The effect of Christians on society as a whole should be to improve society as a whole.  This mandate is, therefore, a command to have an impact on society, drawing general society to be a better reflection of God and his law, not simply a call to evangelize.  Part of that is to have a social and political impact on society.
Furthermore, there is ample evidence in scripture that entirely reprobate societies are subject to God's judgement (witness Sodom and Gomorrah, the Noahdic flood, the Canaanites, etc).  It is also worthwhile to examine the rise and fall of all empires in history; nearly all mark the end of their influence with reprobate societies, in particular of a sexual nature.
Apart from that, Christians have historically been deeply involved in society and social issues.  This is because Christians "impose" their "values" onto those around them - specifically that all humans have inherent dignity and inherent "God-given" rights in keeping with that dignity.
So, I would say that Christians have a moral duty and obligation to have an impact on their society.  Being involved in social-political issues, including law-making, is a part of that.
Now that being said, we do have to be careful of exactly what stand to take and how we go about taking it.


"If a sin can be dispensed, is it really a sin?"

No, a sin which is dispensed of could never be a sin, because a sin is an offense to God, and offending God can never be excused.

"Does the Church have the power to declare that something is now a sin which was not previously a sin, and to declare that something is no longer a sin which was previously a sin?"

No, the Church cannot dispense someone from their moral duty as creatures of God to avoid sinful activity.

However, the Church can remove the obligation to do something in a certain way (i.e. attend Mass as a species of activity which falls under the genus 'keeping holy or separate the Sabbath day'). By removing the obligation, they remove the possibility of contravening any law, because it is no longer binding.

In this case, the Church has not modified what is intrinsically sinful (excusing people from offending God), but have modified what Christians are bound by obedience to the Church to do.

To use @Geremia's example: if a parent tells their child not to eat a cookie, it is wrong to for that child to eat the cookie. If a parent then permits the child to eat a cookie, then it is not wrong for the child to eat the cookie. In this instance, eating cookies, or not eating cookies is utterly irrelevant - only the obedience to one's parents.

Similarly, every Christian has the moral duty to obey the commandments of the Church as their legitimate authority and teacher - and per the perennial trope, mother. Attending or not attending Mass is not intrinsically or inseparably related to keeping holy the Sabbath day, as is proven by the sheer fact that the Mass did not exist until Calvary - one thousand years after the commandment was issued by God.

Attending Mass is one of many ways to keep holy the Sabbath day, and thus is not necessarily commanded by the commandment to keep holy the Sabbath day (i.e. where Christians have always viewed Sunday as the new Sabbath of Christians).

Thus, the Church, in her prudence, or even simply by her authority, has the right to bind or loose the obligation to attend Mass on Sunday, without touching the sinfulness of obedience, which remains, whether one is bound by obedience to attend Mass on Sunday, or freed from the obligation by the Church. To date, the Church has not seen any good reason to dispense anyone from attending Mass every Sunday except for relatively extreme travel requirements, illness, or, apparently, in times of the current crisis.

"Why are the sins of murder and missing Mass treated so differently? What is the fundamental difference between the two? Do they have the same degree of severity?"

A mortal sin is simply any sin which leads to spiritual death (hence "mortal," which means "causing death"). This doesn't imply that all sins which are mortal have the same severity, incur the same punishment in hell (or temporal punishment, if forgiven). A child abuser will incur more punishment for his sin, than someone who elects not to travel to attend Mass because he has a bad case of the sniffles. For reasons that should be obvious. Murder is obviously worse than wilfully lying about a non-trivial matter (such as making a false oath). Homosexual fornication is obviously worse than heterosexual fornication, because it involves at least one more degree of deviation from God-ordained sexual relations than does heterosexual. Etc.

That is, while venial and mortal sins designate two manners of sinning, they don't imply that all venial, or all mortal, sins are the same as every other, or carry the same penalty.


If both the Orthodox and Catholic Church affirm salvation by grace through faith, why did the Protestant Reformation happen?

Because the Catholic Church doesn't teach that we attain salvation only through the reception of God's grace by faith. That's why the Protestant teaching is called sola fide!

The Catholic Catechism says:

  CCC 2010 Since the initiative belongs to God in the order of grace, no one can merit the initial grace of forgiveness and justification, at the beginning of conversion. Moved by the Holy Spirit and by charity, we can then merit for ourselves and for others the graces needed for our sanctification, for the increase of grace and charity, and for the attainment of eternal life. Even temporal goods like health and friendship can be merited in accordance with God's wisdom. These graces and goods are the object of Christian prayer. Prayer attends to the grace we need for meritorious actions.

And the Council of Trent declared:

  Canon xxiv. If any one shall say, that the justice received is not preserved, and also increased in the sight of God through good works; but that the said works are merely the fruits and signs of justification received, but not a cause of the increase thereof; let him be anathema.

  Canon xxxii. If any one shall say, that the good works of a man that is justified are in such wise the gifts of God, as that they are not also the good merits of him that is justified; or, that the said justified, by the good works which are performed by him through the grace of God and the merit of Jesus Christ, whose living member he is, does not truly merit increase of grace, eternal life, and the attainment of that eternal life, if so be, however, that he depart in grace, and, moreover, an increase of glory; let him be anathema.

So while the Catholic Church affirms that we cannot merit "the initial grace of forgiveness and justification" it does teach that our good works merit the completion of our sanctification and our full attainment of salvation and eternal life. It also condemns the Protestant teachings that good works are only the gifts, fruit, and signs of justification but do not merit eternal life.

As to the Eastern Orthodox churches, I know much less about them, but I did find this catechism. If I'm understanding correctly, it teaches a rather sacramental understanding of salvation, in which participation in the sacraments is necessary. Protestants would say this too is not compatible with salvation by grace alone through faith alone, as well as the doctrine that Christ is our only mediator (ie, Christ alone).

  The Church is not a building, but a People who are filled with the Holy Spirit and who share in His life bringing His life into the world. It is through the
  sacraments of the Church that we are united to Christ. (p77)

Rather than the Protestant teaching that we are united to Christ by the Holy Spirit through faith.

  Since they [the sacraments] were initiated by Christ Himself, or by the implicit request
  of Christ, they are necessary for our salvation. They were instituted as a
  means of transmitting Grace based on the needs of the believers. This
  is not to limit the action of the Holy Spirit as it can surely act outside
  of these ceremonies. But, Grace can only be received through Baptism
  and the Eucharist which were directly established by Christ. (p92)

  Yet, no matter how great our repentance is, if it is not completed by
  the Mystery of Confession it does not give rise to salvation or reconcile
  us with God. It is only through Confession preceded by the sincere
  repentance that our sins can be cleansed and our soul be healed. Repentance alone is not sufficient. (p109)

  There is no doubt that God accepts the repentance of a sinner,
  but He forgives it only through the medium of the spiritual Father [a priest] and
  the Mystery of Confession. (p110)


Have the individual commands of the OT Law ever been categorized as "Moral," "Ceremonial," and "Civil?"

There is no risk in saying that no well known person has ever tried to categorize all of the commands of the Old Testament into moral, ceremonial and civil categories. The reason is that although it is helpful to consider the Law among those divisions Christians have never felt it that important to do so.  Christians do not even have a unanimous view on wether the commandment in the 'Ten Commandments' to obey the Sabbath, it moral, civil, or ceremonial.

For example:

  In Sabbatarian apologetic, it is common to distinguish between moral, ceremonial, and civil law. The Sabbath commandment is then thought to be binding on all, not only because it is alleged to be a “creation ordinance,” but also because it is part of the Decalogue, which is classified as “moral.” The distinction between moral, ceremonial, and civil law is apt, especially in terms of functional description, but it is not self-evident that either the Old Testament or New Testament writers neatly classify Old Testament law in those categories in such a way as to establish continuity and discontinuity on the basis of such distinctions. Even if such categories are applied, it should be noted that both David’s law-breaking and that of the priests (found only in Matthew) come from ceremonial law. It is difficult, then, to resist the conclusion that their applicability to the Sabbath case puts Sabbath law in the ceremonial category with them. (Carson, From Sabbath to Lord’s Day, “Jesus and the Sabbath in the Four Gospels,” pp. 68–69.)

If Christians can't agree on how to classify the Ten Commandments under this scheme (which I still think is very useful) how would one even attempt to denominate every precept in the Old Testament strictly under it?

I think it is fair to say that in general Christians at the time of the Apostles understood that the ceremonial law was obsolete, that separation of Jew and Gentile was obsolete and that love for God and one's neighbor summed up 'whatever' was not obsolete in Christ. They also recognized the moral law in some form existed before Moses.

The freedom was so great and the glory so grand, that there was no need to strictly define everything.  Rather to allow for the weaknesses of individuals who held to traditions of their upbringing, as well as the ignorance of some who had no moral upbringing at all, a culture of tolerance over the subject was adopted as it did not matter.  The only time it did matter is when someone tried to add a condition to faith as a requirement to be a 'real' or 'strong' Christian.  Then the Apostles made a strong stance.   For example, if someone thought circumcision had some value then Paul would say:

  Circumcision is nothing and uncircumcision is nothing. Keeping God’s commands is what counts. Each person should remain in the situation they were in when God called them. (ESV 1Co 7:19-20 )

However, if someone tried to pressure others to be circumcised he would then say it differently:

  Mark my words! I, Paul, tell you that if you let yourselves be circumcised, Christ will be of no value to you at all. (ESV Gal 5:2)


How could I bring up security concerns at the church that I attend?

Uniformed security at a church is uncommon enough that you can use it as a conversation opener.

If I were you I would seek out a (non-clergy) trustee / deacon / elder / congregation-council member / whatever and simply ask "what's up with the guards?"  That should open the topic, and you will likely learn something about the congregation's history and struggles.

How do you find the person to talk to if you don't already know them? Easy: ask a person who serves coffee for an introduction.

Believe me: asking polite questions of lay leaders honors their offices; they'll love it. Don't hesitate.


Have any 20th/21st century Ecclesiologists developed a framework/models for describing/categorising the functions of the visible church?

I have yet to find an academic book or a journal article that provides a research-level model for what a church does.  Most I found is on the nature of the church, similar to Avery Dulles's 1987 book Models of the Church, such as Stanko Jambrek's 2019 journal article Church Models for the 21st Century where he reviews a variety of church models in 3 categories (1. formed today, 2. created throughout history, 3. have a foundation in the Word of God).  The article also includes an analysis of Dulles's model.
However, below are some pointers for your literature review to come up with a good list/model of what a church does for your coding frame.
Enduring church functions
For a church to thrive and blessed by the Holy Spirit, the church needs to be aware of its proper mandate.  Based on the Acts of the Apostles, The Letters of Paul, and the Pastoral Epistles, Rev Mark Feldmeir wrote The Five Functions of the Church for the Clergy Academy of the Mountain Sky Conference of the United Methodist Church:

Training - Didache
Worship - Liturgia
Community - Koinonia
Service - Diakonia
Proclamation - Kerygma

How a church implement the NT mandate and organize their activities is of course heavily dependent on its denomination.  For a representative example of a Protestant church read the article Church: Six Functions of the Church or for a typical non-denominational Baptist church read the 2019 Southern Baptist Journal of Theology article What are the Essentials of a Local Church?  Guidelines for Missionary Ecclesiology which enumerates a local church's functions as follows:

Worship: public singing, teaching, admonition, celebration of ordinances, giving, testimony, mutual encouragement
Preaching and Teaching:
Prayer: adoration, confession of sin, thanksgiving, supplication, intercession
Baptism and the Lord's Supper:
Discipleship: individual exhortation, encouragement, mentoring
Fellowship: build each other up, serving one another, bear one another's burden, etc.
Accountability and Discipline: intertwined with both discipleship and fellowship
Generous Giving: to relieve the poor, to advance the gospel around the world, etc.
Evangelism:
Missions:

Another way to bring out what a church does is by examining the church officers mentioned in the New Testament:

Presbyters: Responsible for teaching, preaching, baptisms, pastoral care, leadership, management
Elders: Responsible for governing and internal affairs
Deacons: Responsible for external affairs including the caring side of the church, including ministering beyond the community of faith

To the above NT offices many Protestant churches today add / subsume new offices to complete their church organization and hierarchy with:

Ministries: Sunday school, adult education, music, women's group, men's group, etc.
Support groups: grief sharing, divorce recovery, substance abuse, etc.
Missions:

local projects: soup kitchen, homeless shelter, etc.
regional projects: home repair, habitat for humanity
international projects: schools, hospitals, orphanages, missionaries

Committees: Nominating, Hospitality, Personnel, Finance, Stewardship, etc.
Board of Trustees: responsible for the property of the church

(source: Don's empirical notes on church officers and church organization, better source to be found)
Church administration and church leadership books
I found that Church administration and church leadership books, especially the handbook / reference style ones, can help populate your coding frame.  For example, see the detailed Table of Contents of The Church Leader's Answer Book: A Reference Guide for Effective Ministry which covers (what I think) every foreseeable activity that a church might do to implement the above church functions effectively, although I admit that this book seems to be written more for non-sacramental / non-liturgical / non-denominational churches, and therefore is missing some aspects of what Lutheran / Anglican / Catholic churches are doing.
To give an idea, these are the book's part headings, which in turn are subdivided into about 5-8 chapters each:

Administration: Church Management, Church Boards, Meetings, Decision Making, Pastoral Search, Staffing, etc.
The Church Office: People, Place, Procedures, Storing Documents, Equipment, etc.
Change and Conflict:
Construction and Renovating: Deciding, Building Trends, Builders and Architects, Financing, Location, Planning
Facilities and Operations:
Church Furnishings:
Church Finances: Budget, Borrowing, Grants, Giving, Investments, Taxes, etc.
Leading Others: Identifying Gifts, Mentoring, Coaching, Making Disciples, etc.
The Pastor's Life: Family, Growth, Rest, Finding your place of ministry, etc.
Preaching: Audience, Applying the Word, Planning, Style & Delivery, Illustration, Technology, etc.
Groups for Growth: Planning programs, Children's Programs, Youth Programs, Prayer Groups, Small Groups, Singles, Special-Interest Groups
Pastoral Tools: Counseling, Special Visits
Community Outreach: Becoming Outwardly Focused, Assessing Your Community, Meeting Community Needs, Finding Lost People, Assimilating Newcomers, Missions
Worship: The Heart of the Worship Leader, Laying the Groundwork, Worship Planning, Worship Leaders and Teams, Technology, Special Services


Why did not Jesus praise John the Baptist before the latter's disciples?

TL;DR: Jesus was not disappointed and St. John the Baptist did not have doubt.  Some Church Fathers interpreted the passage to mean that either

John the Baptist was sending the disciples for their sake (so v.6 was directed at the disciples), or

the reference "the one who will come" meant John was asking "whether Jesus also would come into the underworld so that John could proclaim him as the forerunner there also after his death." (see Hermeneia commentary below and catena aurea on Matt 11).

The rest of this answer is based on Volume 2 of the Hermeneia commentary on the Gospel of Matthew, which is a commentary emphasizing technical exegesis and history of interpretations rather than theological, so I believe it can apply for the Catholic point of view as well, as it covers the view of the Church Fathers.
Verse 11:6 is treated under "The Baptist's Inquiry (11:2-6).  I'm skipping the Analysis portion (Origin, Redaction, Source) which discusses the authenticity of the pericope text before final redaction and the verse by verse Interpretation.

History of Interpretation (verse 3)
Why does the Baptist, who—for both the church and the evangelist!—had proclaimed Jesus as the coming one, suddenly become a doubter? The question angers Luther. “Most of what I can find written about this gospel deals with the question of whether St. John did not know that Jesus is the rightful Christ; but that is an unnecessary question, and it is of no great consequence.”26 In the ancient church Tertullian, among others, dared to say that John had doubted Jesus’ messiahship27, but he encountered unanimous and indignant protest. The usual answer was that John had asked Jesus not for his own sake but for that of his disciples.28 Beginning with Origen a number of interpreters have understood “the one who will come” with a future meaning and have interpreted John’s question just before his own death as asking whether Jesus also would come into the underworld so that John could proclaim him as the forerunner there also after his death.29 Since the Enlightenment, Protestant exegesis has again taken seriously the possibility that John genuinely doubted. Depending on one’s theological position, the interpretations have gone in different directions. Some found it to be understandable that even brave men would experience all kinds of doubts and anxieties in a prison cell.30 Another was confident that doubt is part of a prophet’s “religious condition.”31 Widespread is the thesis of the Baptist’s messianic impatience whose doubts came simply from the fact that Jesus delayed his messianic revelation too long.32 It was said that such impatience would also be understandable in a prison cell! At the same time, it was said, there are obvious pedagogical reasons why Jesus delayed. He wanted first to win the hearts of the people.33 Knabenbauer announces, not without pride, that in his time “practically all” Protestants believed that John doubted Jesus’ messiahship, while the Catholics attempted to remove from him any shadow of doubt.34
[Some footnotes]
Joseph Knabenbauer, Commentarius in Evangelium secundum Matthaeum, 2 vols. (Cursus scripturae sacrae 3/1–2; 3d ed.; Paris: Lithielleeux, 1922).
29 Since Origen Hom. in 1 Reg. 28.3–25 = GCS Origenes 4.290.30–32. In the West this interpretation was spread through Jerome (77–78); idem Ep. 121.1 ad Algasiam = CSEL 56.5 on the basis of the translation in the Vulgate “qui venturus es” (future). Cf. Daniel Sheerin, “St. John the Baptist in the Lower World,” 1–22, 7–17; later material in Simonetti, “Praecursor” 372–82.
Manlio Simonetti, “Praecursor ad inferos: Una nota sull’ interpretazione patristica di Matteo 11, 3, ” Augustinianum 20 (1980) 367–82.

Commentary's Interpretation:

3 There is no indication that Matthew would have seen John’s doubt as a problem. However, since in his entire gospel he strongly Christianizes the Baptist,36 precisely in his gospel John’s question is somewhat strange. Do we have here simply traditional material passed along unthinkingly? Or is the basic aspect of John’s question important for Matthew? Are people to approach Jesus as openly as John (and his disciples!) in order to give Jesus an occasion for talking about his activity? In that case the skeptical crowds are compared with John’s disciples after they have left (vv. 7–19*). Then John and his disciples would be important not so much as individual figures but as representatives of that part of Israel that was favorable toward Jesus. However, none of that is stated explicitly.
4-5 (skipped)
6 Only in the concluding macarism of v. 6* is the person of Jesus mentioned explicitly. Σκανδαλίζω, a late Jewish and Christian word, means “to set a trap,” “to erect an obstacle,” then more generally “to give offense,” “to lead to ruin,” “to seduce to sin.” Ἑν designates the person or thing through which the offense comes. In Matthew (and Mark), the word is used of the final abandoning of Jesus in the passion (26:31*, 33*) and in the end-time (24:10*). Our text looks ahead to these texts and to 13:57*; 15:12*. The general formulation in the third person shows that more is involved than a warning to John’s disciples.47 Instead, here at the conclusion is the christological-parenetic point of our text that is fundamental for the evangelist. He is concerned not that one should have the right knowledge about Jesus but that one not reject the experiences of salvation to which Jesus extends an invitation. These experiences of salvation make a claim; they require a decision for or against Jesus. It is for just this reason that the evangelist, after Jesus’ healing ministry in Israel (chaps. 8–9), had Jesus give the disciples the task of confronting Israel with a decision (chap. 10)
Summary [for 11:2-6]
First of all, the meaning of our text must be determined on the basis of Matthew’s entire story. After the programmatic proclamation and the miracles of Israel’s Messiah, Israel must respond to the question of who Jesus truly is. It can respond not by formulating a correct messianic answer but only by actually becoming part of the story of Jesus and by letting the story bring it to a life decision about Jesus. Our text is a model of how Matthew takes christological titles and concepts into his story of Jesus and subordinates them to it. It is a model of what is called narrative Christology and of how it lays a claim on people. Thus Matthew uses the Baptist and his disciples to show the way of understanding “on which the disciples also had to go and on which the people should go.”49 What is important is that one become part of the story, the deeds of the Christ. No “abstract” christological answer can replace this participation in the story of the Christ. The Baptist and his disciples demonstrate positively the possibility of salvation for Israel.50 The continuation of the story will then clarify, in the form of prophetic warnings whose central figure is once again John the Baptist, the negative possibility—Israel’s no.


Does the Catholic Church have a standard instruction on placing crosses on the altar?
The Crucifix is placed on the altars in the Roman Rite is placed to recall to the mind of the celebrant, and the people, that the Victim offered on the altar is the same as was offered on the Cross.

Altar-Crucifix. — The crucifix is the principal ornament of the altar. It is placed on the altar to recall to the mind of the celebrant, and the people, that the Victim offered on the altar is the same as was offered on the Cross1. For this reason the crucifix must be placed on the altar as often as Mass is celebrated (Constit., Accepimus of Benedict XIV, 16 July, 1746). The rubric of the Roman Missal (xx) prescribes that it be placed at the middle of the altar between the candlesticks, and that it be large enough to be conveniently seen by both the celebrant and the people (Cong. Sac. Rit., 17 September, 1822). If for any reason this crucifix is removed, another may take its place in a lower position; but in such cases it must always be visible to all who assist at Mass (ibid.). We remarked above that a crucifix must be placed on the altar during Mass. To this rule there are two exceptions:

when the Crucifixion is the principal part of the altarpiece or picture behind the altar. (We advisedly say the principal part of the altarpiece or picture, for if the picture represents a saint, e.g. St. Francis Xavier holding a crucifix in his hand, or St. Thomas kneeling before the cross, even if the cross be large, such a picture is not sufficient to take the place of the altar-crucifix -- see Ephem. Lit., 1893, VII, 408) and

when the Most Blessed Sacrament is exposed.

In both these cases the regular crucifix may be placed on the altar; in the latter the local custom is to be followed (Cong. Sac. Rit., 2 September, 1741), and if the crucifix is kept on the altar it is not incensed (29 November, 1738). From the, first Vespers of Passion Sunday to the unveiling of the cross on Good Friday, even if a solemn feast occur during this interval, the altar-crucifix is covered with a violet veil (Cong. Sac. Rit., 16 November, 1649), except during High Mass on the altar at which Mass is celebrated on Holy Thursday when the veil is of white material (Cong. Sac. Rit., 20 December, 1783), and on Good Friday, at the altar at which the function takes place, when the veil may be of black material. This is the custom in Rome (Martinucci, Van der Stappen, and others). From the beginning of the adoration of the Cross, on Good Friday, to the hour of None, on Holy Saturday inclusively, all, even the bishop, the canons and the celebrant, make a simple genuflection to the cross (Cong. Sac. Rit., 9 May, 1857; 12 September, 1857). At all other times during the year a simple genuflexion is made to the cross, even when the Blessed Sacrament is not kept in the tabernacle, during any function, by all except the bishop, the canons of the cathedral, and the celebrant (Cong. Sac. Rit., 30 August, 1892). The altar-crucifix need not be blessed; but it may be blessed by any priest, by the formula "pro imaginibus" (Rituale Rom., tit. viii, cap. xxv). It may be well to note that if, according to the Renaissance style of architecture, the throne is a permanent structure above the tabernacle, the altar-crucifix may never be placed under the canopy under which the Blessed Sacrament is publicly exposed, or on the corporal which is used at such exposition (Cong. Sac. Rit., 2 June, 1883). It is probable that the custom of placing a crucifix on the altar did not commence long before the sixth century. Benedict XIV (De Sacrificio Missae, P. I, 19) holds that this custom comes down from the time of the Apostles. However, the earliest documentary evidence of placing a cross on the altar is canon III of the Council of Tours, held in 567: "Ut corpus Domini in Altari, non in armario, sed sub crucis titulo componatur". Mariano Armellini (Lezioni di Archeologia Sacra) tells us that the early Christians were not accustomed to publicly expose the cross for fear of scandalizing the weak, and subjecting it to the insults of the pagans, but in its stead used symbols, e.g. an anchor, a trident, etc. A simple cross, without the figure of Christ, was fixed on the top of the ciboria which covered the altars.

A little historical note for those interested:
During World War II, Catholic Chaplains of the Roman Rite were permitted to use of the Eastern Rite Antimension when celebrating Mass outside of churches, for the troops during the war. Thus mass could be celebrated close to the front lines of war without a bulky altar stone.

An antimension ofThe Byzantine Altar

Q: Can an antimension still be made in the Latin Church? The old Rituale Romanum specifies the blessing of one, and how it must be made, but I am unaware of any post-conciliar legislation. If obtaining new antimensia in the Western Church is not possible, could a priest request that a hierarch of the Eastern Church bless one, in accordance with their customs?
A: An antimension, from the Greek for "instead of the table," is among the most important furnishings of the altar in Byzantine Christian liturgical traditions. It is a rectangular piece of cloth, of either linen or silk, typically decorated with representations of the entombment of Christ and the four Evangelists and scriptural passages related to the Eucharist. A small relic of a martyr is sewn into it. The Eucharist cannot be celebrated without an antimension that must be consecrated by a bishop and indeed is given to the priest by the bishop as a witness to his permission to celebrate the Divine Liturgy.
The antimension is a substitute for the altar table. A priest may celebrate the Eucharist on the antimension even if the altar table is not properly consecrated. In emergencies, when an altar table is not available, the antimension serves a very important pastoral need by enabling the use of unconsecrated tables for divine services outside of churches or chapels.
In the Latin tradition, Mass was celebrated with an altar stone containing a small relic. When celebrating outside of a church with a consecrated altar, a portable altar stone was used. After the Turkish conquest of the Byzantine Empire in 1454, however, many Eastern Christians, Greeks and Albanians fled to southern Italy. Some submitted to Rome while retaining their rite, but the faith of others was doubtful. Since some Latin priests began to use the antimensia there was a fear that celebrating on their antimensia was consequently considered as a communion in sacred things (Communicatio in Divinis) with heretics, and therefore forbidden.
Hence the popes, notably Clement VIII (1592-1605) and later the great canonist Benedict XIV (1740-1758), regulated the practice. Benedict XIV in his document "Etsi Pastoralis," promulgated May 26, 1742, determined the following:
"If the Greeks wish to accept portable altars consecrated by Latin Bishops, it would be well; if they do not wish to do so, the placing of their antimensia, or thrones, on stone altars when they celebrate, may be tolerated. They should use Corporals like the Latins, unless they use their thrones also as Corporals. It is not lawful for a Latin Priest celebrating in the Latin Rite in churches of the Greek Catholics, if he lacks his own portable altar stone, to celebrate the Sacrifice of the Mass on the antimensia, or thrones, of the Greeks. Every Priest must celebrate with a chalice of gold, or only silver or at least tin [pewter?], using a Throne or Corporal of linen, white and clean, and an altar covered with clean altar-cloths or with decently prepared ornamental covering."
These limitations were formally incorporated into the 1917 Code of Canon Law (Canon 823.2):
"In the absence of an altar of his own rite, it is fundamental that a priest can celebrate his own rite on an altar consecrated in another Catholic Rite, but not on the antimensiis (altar cloths) of the Greeks."
In spite of these prohibition, however, many exceptions and indults were granted to individual bishops and priests and to missionary societies to use a form of antimension to celebrate Mass on portable altars.
During the Second World War, the Holy See granted to military chaplains the privilege of using for the celebration of Mass, instead of the Latin-rite portable altar stone, "a veil which had enclosed, and well fastened, authentic relics." This was later extended to peacetime military activities. Since it was not always possible to obtain a veil with authentic relics, the use of an Eastern-rite antimension was considered an acceptable alternative.
Finally, Paul VI's "Pastorale Munus," a letter issued "motu proprio" (on his own initiative) in November 1963, gave to all local ordinaries of the universal Church (of all rites, Western and Eastern) the faculty to grant, for a just and serious reason, to all priests subject to them, who enjoy the faculty of the portable altar, the faculty of substituting for the portable altar stone the Byzantine or the Latin forms of the antimension.
Although this faculty has not been revoked, it has, in a way, been superseded by later liturgical legislation which no longer requires the use of an altar stone for portable altars and foresees the use of relics in fixed altars only if they are visibly part of a human body.
Finally, we present the text of the blessing of the Latin form of the antimension approved by the Congregation of Sacred Rites on March 12, 1947. The use of the antimension still required a special apostolic indult for it to be used in the celebration of Mass in mission territories, in place of an altar-stone or portable altar. It was reserved to a bishop but could be delegated to a priest. - Use of an Antimension in the Latin Church


In what way is the Son of God "one with the Father"?

The Trinitarian position on this is pretty straight forward. Hard to wrap your mind around, maybe. A mystery, sure. But the same basic idea is held by most Trinitarians, especially Protestant and Catholic traditions. Eastern Orthodoxy comes at this from a rather different angle, but as far as application to that verse goes aren't fundamentally different.

Jesus is one substance with God the Father. In other words he was and is God incarnate, not some created being, not a lesser creature, not a mirage, really and truly the one true God in physical form.

The Athanasian Creed is a good reference for this point:

  Now this is the catholic faith:

Note the little-c catholic here is not a reference to Roman Catholicism, it just means universal.

  That we worship one God in trinity and the trinity in unity,
  neither blending their persons
  nor dividing their essence.
  For the person of the Father is a distinct person,
  the person of the Son is another,
  and that of the Holy Spirit still another.
  But the divinity of the Father, Son, and Holy Spirit is one,
  their glory equal, their majesty coeternal.

That's the basic outline of what the Trinity is: three persons but one being.

Now here's the part that directly addresses that verse. It says basically the same thing over in a lot of ways just to eliminate as much confusion as possible and not leave wiggle room for novel definitions:

  What quality the Father has, the Son has, and the Holy Spirit has.
  The Father is uncreated,
  the Son is uncreated,
  the Holy Spirit is uncreated.

  The Father is immeasurable,
  the Son is immeasurable,
  the Holy Spirit is immeasurable.

  The Father is eternal,
  the Son is eternal,
  the Holy Spirit is eternal.

  And yet there are not three eternal beings;
  there is but one eternal being.
  So too there are not three uncreated or immeasurable beings;
  there is but one uncreated and immeasurable being.

  Similarly, the Father is almighty,
  the Son is almighty,
  the Holy Spirit is almighty.
  Yet there are not three almighty beings;
  there is but one almighty being.

  Thus the Father is God,
  the Son is God,
  the Holy Spirit is God.
  Yet there are not three gods;
  there is but one God.

  Thus the Father is Lord,
  the Son is Lord,
  the Holy Spirit is Lord.
  Yet there are not three lords;
  there is but one Lord.

  Just as Christian truth compels us
  to confess each person individually
  as both God and Lord,
  so catholic religion forbids us
  to say that there are three gods or lords.

  The Father was neither made nor created nor begotten from anyone.
  The Son was neither made nor created;
  he was begotten from the Father alone.
  The Holy Spirit was neither made nor created nor begotten;
  he proceeds from the Father and the Son.

  Accordingly there is one Father, not three fathers;
  there is one Son, not three sons;
  there is one Holy Spirit, not three holy spirits.

  Nothing in this trinity is before or after,
  nothing is greater or smaller;
  in their entirety the three persons
  are coeternal and coequal with each other.

A couple paragraphs later it gets into more specifically how this relates to the Son's incarnation. Obviously him taking on human nature adds an extra wrinkle to the whole thing, so it points out that this doesn't nullify the basic Trinitarian formula:

  That we believe and confess
  that our Lord Jesus Christ, God's Son,
  is both God and human, equally.

  He is God from the essence of the Father,
  begotten before time;
  and he is human from the essence of his mother,
  born in time;
  completely God, completely human,
  with a rational soul and human flesh;
  equal to the Father as regards divinity,
  less than the Father as regards humanity.

  Although he is God and human,
  yet Christ is not two, but one.
  He is one, however,
  not by his divinity being turned into flesh,
  but by God's taking humanity to himself.
  He is one,
  certainly not by the blending of his essence,
  but by the unity of his person.
  For just as one human is both rational soul and flesh,
  so too the one Christ is both God and human.


Is it possible to be a Christian by birth?

No.

God knows each one of us as a person, not just part of a family. This is clear even in the Old Testament:

  Ezekiel 33:20 (ESV)
  Yet you say, 'The way of the Lord is not just.' O house of Israel, I will judge each of you according to his ways."

Looking at the Gospel in the New Testament, we see that again each of us is an individual to God:

  John 3:16 (ESV)
  "For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life.

God saves whoever believes in Jesus from perishing. Only by believing, yourself, can you be saved.


Does the Catholic Church have a contingency plan for the case that the pope and all cardinals are dead?

There is no known official contingency plan for the Catholic Church in the case that if God forbid the pope and the entire College of Cardinals were to perish due to some unforeseen catastrophic event such as a terrorist attack or some highly contagious pandemic like the coronavirus during a papal election!

Ultimately, the Holy Spirit would through his inspirations would guide the Church in choosing another pope and thus a new pope could name cardinals of his choosing.

First of all let us remember what Our Lord said to St. Peter in Matthew 16:17-19:

  17 And Jesus answering, said to him: Blessed art thou, Simon Bar-Jona: because flesh and blood hath not revealed it to thee, but my Father who is in heaven.

  18 And I say to thee: That thou art Peter; and upon this rock I will build my church, and the gates of hell shall not prevail against it.

  19 And I will give to thee the keys of the kingdom of heaven. And whatsoever thou shalt bind upon earth, it shall be bound also in heaven: and whatsoever thou shalt loose upon earth, it shall be loosed also in heaven.

Thus as Catholics, we are assured that the Church will exist to the end of time and will be guided and protected through the inspirations of the Holy Spirit.

But how could this possibly be if the papacy and the entire body of the Sacred College of Cardinals were to die simultaneously?

Obviously there can not be many possible solutions as to how a new pope could be named and thus new cardinal electors could be forthcoming. However a few possible scenarios could happen.

There is no guarantee that there would be any need for a pope or cardinals at the moment of Our Lord’s second coming, according to Sacred Scriptures which guaranties only that the gates of hell shall not prevail against her. Thus this could simply be a prelude to the end of the world. The pope and cardinals would certainly not be necessary when the Jesus returns as Head of the Church!
Each pope generally makes a last will and testament. A particular pope could under his unique apostolic authority name his successor if he so wish to. A pope does not have to be chosen from the ranks of the cardinals. Any baptized Catholic male could in theory be elected pope. At one time, it had been rumoured that Pope Pius XII wrote a letter that was to be published in the case he was taken prisoner by the Germans during World War II. In it he supposedly stated that he rescinded his rights as Pope Pius X if he was taken by the Nazis and was to once again Cardinal Eugenio Pacelli. For more information about this possibility see this post: Can a pope name his successor?
The most viable solution, would be that either the remaining Roman clergy and/or local bishops surrounding Rome would elect a successor to the See of St. Peter, in lieu of the College of Cardinals. In fact this was how the pope was elected for centuries before Canon Law and various papal documents defined how a papal election was to be handled.  (If need be the choice of naming a new bishop could be extended to all the remaining bishops of Italy.)

  In 1059, the right of electing the pope was reserved to the principal clergy of Rome and the bishops of the seven suburbicarian sees. In the 12th century the practice of appointing ecclesiastics from outside Rome as cardinals began, with each of them assigned a church in Rome as his titular church or linked with one of the suburbicarian dioceses, while still being incardinated in a diocese other than that of Rome.

  The term cardinal at one time applied to any priest permanently assigned or incardinated to a church, or specifically to the senior priest of an important church, based on the Latin cardo (hinge), meaning "pivotal" as in "principal" or "chief". The term was applied in this sense as early as the 9th century to the priests of the tituli (parishes) of the diocese of Rome.

Seeing that Canon Law is silent on this situation, simply because it is simply speculative and highly doubtful of actually occurring, the most simple solution would be that the world’s bishop would opt to this most ancient form of voting for a new Bishop of Rome.

If only the pope and the Roman Curia where destroyed as if a hydrogen bomb was detonated in the Colosseum of Rome, effectively wiping out the entire Roman Curia, there would still remain enough cardinals worldwide to elect a pope and start rebuilding!

In any case the Church would find a way and it would be aided by the Holy Spirit.

Here follows a couple of related questions which although similar, are not duplicates to this particular question:

What would the Catholic Church's hierarchy look like without the Vatican?
What would happen to the Catholic Church if all of the bishops get wiped out?
Existence of Catholic Church without hierarchy

Nota Bene: Perhaps a future pope reading this post could make amends to Canon Law accordingly to include such dire situation scenarios for the papal elections as mentioned above?


Was the Apostolic Tradition of rejecting soldiers from the church ‘permanent’, or was this ‘tradition' briefly enforced?

This answer is based on the article Christians and the Roman Army AD173-337 by John Helgeland (Church History 43(2):149-163, 200; 1974). The start date of AD173 is the year when we have the first evidence (after the NT) of Christians in the military - in Legio XII Fulminata (the Lightning Legion) under Marcus Aurelius.

Prohibitions on members of the (Roman) military becoming Christian were not universally enforced, and there was disagreement among the Fathers as to whether it was possible to be Christian and a soldier at the same time. Certainly Christians should not take part in persecutions. Torture and capital punishment (for which officers were responsible) were also identified as wrong. On the other hand, the ordinary work of the army was not necessarily considered to be bad. Clement of Alexandria (Protrepticus 10) sees it as just another profession, and Tertullian in his early writings urged Christians to pray for the Empire and her armies (Apology 30):

  Without ceasing, for all our emperors we offer prayer. We pray for life prolonged; for security to the empire; for protection to the imperial house; for brave armies, a faithful senate, a virtuous people, the world at rest, whatever, as man or Cæsar, an emperor would wish.

Origen believed (Contra Celsum 8) that while Christians should not personally serve as soldiers, they should still pray for Roman victory (in wars which were just). In this view, it's not that there's something inherently morally wrong about being a soldier - but only that it is problematic for a Christian to serve in a non-Christian army, for a non-Christian empire.

A related problem was that Roman military service was bound up with Roman religion; Tertullian's On idolatry identified the taking of an oath to the state to be un-Christian, and moreover, Roman military standards (signa militaria) were given special reverence, placed in a sanctuary in the camp so that soldiers could pay homage - these were signs of the gods-given authority of the emperor. Origen, similarly, said that since all authority comes from God, it is not right to give this honour to Caesar. Several Christian soldiers were martyred towards the end of the third century for refusal to perform army rites, objection to the idolatrous nature of the signa militaria, etc. This was intensified under the persecution of Diocletian, who issued edicts to require all soldiers to take part in sacrifices and other rites - the intention being to get rid of Christians in the army, which implies that there must have been a substantial number of Christians there to be purged. So any prohibition on military service, on the part of Christian leaders, was not being well enforced at this time.

After the conversion of Constantine to Christianity, the force of many of these objections was removed, and subsequent authors find little difficulty in commending Christians to military service. This is the case for Lactantius and Eusebius for example, who were both very pro-Constantine and regarded him as being on a divinely-approved mission. After Constantine we find many graves of soldiers whose inscriptions record their Christian faith in addition to their military service.

In summary, Helgeland argues that the prohibitions in Hippolytus and elsewhere should not be construed as objections to military service in general, but only to the specific idolatrous and persecuting nature of the contemporary Roman army. Moreover, Christian responses differed - some said that Christians should avoid military service entirely, while others would allow it, but on the assumption that the soldier should refuse to participate in evil activities (and accept the consequences).


Why do Catholics bow for icons of the Virgin Mary?

First off, Catholics do not believe Mary is "present in the icon" in the same way we believe Jesus is present in the Eucharist in a particularly physical way (the Eucharist, or physical incarnation of Jesus on Earth, is the only actual physical thing that Catholics worship to my knowledge). Though Mary, like all the other saints (and of course our omniscient God the Father, Son and Holy Spirit), have the power to be present in the world with us, she is not uniquely present in an icon.

Also keep in minds that Catholics do not worship Mary. Worship is reserved only for God, the Holy Trinity. Mary is still a human like us, but also a saint, and she is the most highly revered of all the saints because she represents the perfect model of a Christian fidelity through God's gift to her of being born without original sin, and by her perfect example of obedience to God's will as evidenced in the Bible (you can find more info on that topic here).

So why do we bow, kneel before, or what is better known as "venerate" icons of the Blessed Virgin Mary (or to other icons for that matter)?

An icon is distinct from an idol in that one does not worship the icon or image, but recognizes that it helps us as mortals keep our minds fixed on our prayer toward God through the saints (or Mary in this instance). To expand on this, we believe that Mary, as the only mother of God, has a unique relationship with her son that allows her to intercede for humans in the outpouring of God's graces. We honor Mary and other saints because they are already in Heaven and have this power to intercede for us in a unique way, though one must keep in mind that Mary and the saints have absolutely no power on their own, and that all power and graces come from God.

Icons are symbols or reminders of these facts and serve to help us stay in a holy frame of mind in a similar way to how music enhances our liturgical worship. So though icons are not necessary for prayer, they can be worship aids that greatly enhance our perception of God and the saints among us. This could be extended in a loose sense to why we like to make churches beautiful: to remind us that God is with us and that He is beautiful to the greatest extreme. But no matter what, icons should never, ever become objects of worship- that is idolatry.

Certain icons/images have a more important distinction among the faithful through their miraculous or supernatural origins, Our Lady of Guadalupe  being one such famous example. Because of this, they are generally considered greater representations and reminders of God's greatness and His power to elevate the saints, especially Mary, as models and intercessors for us.

So to answer your question, Catholics bow to images/icons of Mary not because she is present in them, but because of what they represent: the fact that Mary holds the highest position among the saints and her unique role of intercessor for humans. The images are reminders of this fact.

Please keep in mind, my say is not the final say by any means, and there is much more to the theology behind the practice of veneration of images, so I would recommend to do a bit more research if you still have questions (or leave comments and I'll do my best).


What is the difference between Tradition and Revelation according to Catholicism?

First of all, it's important to understand that the Catholic Church does not believe that there has been, nor will be, any new public revelation from God since the Ascension of Jesus; Jesus was "God's Last Word", the full and perfect Word of God. (Perhaps this is what you meant by saying "the Catholic Church believes that there is no direct revelation from heaven to lead the church"?)

Though there have been some private revelations to individuals or groups, and many claimed revelations, none of these belong to the "deposit of faith"—the knowledge and teachings which the Church believes to be divinely sourced and definitively true. This latter kind of knowledge is the revelation of the Word of God Jesus Christ.

This revelation is complete—again, as the Catechism says (quoting St. John of the Cross):

  In giving us his Son, his only Word (for he possesses no other), he spoke everything to us at once in this sole Word—and he has no more to say... because what he spoke before to the prophets in parts, he has now spoken all at once by giving us the All Who is His Son.

(St. John of the Cross, The Ascent of Mount Carmel, 2, 22, 3-5; quoted in Catechism of the Catholic Church paragraph 65)

But though the revelation is complete, the interpretation of what has been revealed to us in and through Christ is ongoing:

  even if Revelation is already complete, it has not been made completely explicit; it remains for Christian faith gradually to grasp its full significance over the course of the centuries.

(Catechism, paragraph 66)

In Catholic understanding, tradition is a part of revelation, just as scripture is. The Gospels and the rest of the New Testament were written down to preserve the message the Church received from Christ; but in addition the apostles handed on

  by the spoken word of their preaching, by the example they gave, by the institutions they established, what they themselves had received—whether from the lips of Christ, from his way of life and his works, or whether they had learned it at the prompting of the Holy Spirit.

(Dei Verbum section 7, quoted in Catechism of the Catholic Church paragraph 76. Dei Verbum is the Dogmatic Constitution [teaching and doctrinal document] on Divine Revelation promulgated by the Second Vatican Council in 1965.)

This orally transmitted part of revelation has come down, the Church believes, directly from the apostles:

  "In order that the full and living Gospel might always be preserved in the Church the apostles left bishops as their successors. They gave them 'their own position of teaching authority.'" Indeed, "the apostolic preaching, which is expressed in a special way in the inspired books, was to be preserved in a continuous line of succession until the end of time." This living transmission, accomplished in the Holy Spirit, is called Tradition, since it is distinct from Sacred Scripture, though closely connected to it.

(Catechism of the Catholic Church, paragraphs 77–78; the quotations are from Dei Verbum again.)

Thus this Tradition is more than just "passed down from one man to another"; it's passed down from the Lord Himself, and from His Apostles, by their divinely instituted teaching authority, and its truth is preserved by the oversight of the Holy Spirit. Through the passing down of this tradition from Jesus, the Holy Spirit remains present and alive in the Church:

  The Father’s self-communication made through his Word in the Holy Spirit, remains present and active in the Church: "God, who spoke in the past, continues to converse with the Spouse of his beloved Son. And the Holy Spirit, through whom the living voice of the Gospel rings out in the Church—and through her in the world—leads believers to the full truth, and makes the Word of Christ dwell in them in all its richness."

(Catechism of the Catholic Church, paragraph 79. The quotation is from Dei Verbum section 8.)

Thus tradition, as one part of the Deposit of Faith, is a source of our understanding of God:

  "Sacred Tradition and Sacred Scripture make up a single sacred deposit of the Word of God" (Dei Verbum 10), in which, as in a mirror, the pilgrim Church contemplates God, the source of all her riches.

(Catechism of the Catholic Church, paragraph 97)


What is the significance of Jesus seeing Nathanael under the fig tree?

Apparently Nathanael took it as evidence of some kind of supernatural knowledge on Jesus' part, but his reaction seems to be overblown - Maybe Jesus just happened to be passing by that tree and recognized him from earlier! I think his dramatic response tells us about Nathanael's personality - impulsive perhaps, certainly an all-or-nothing sort of guy. Someone who is very anxious for the Messiah to appear.

Jesus treats his response with a little bit of humor, it seems. My paraphrase: "You believe all that just because I saw you sitting under a tree? Your going to see much better evidence than that!"

Nevertheless, Nathanael's response is correct, and one of the great confessions of faith, parallel to Thomas' later in the book - "my Lord, and my God!" John may be telling us that great confessions like that, coming from two doubters, are evidence that God chooses to work through the people we'd least expect.


Do good works always express saving faith in Christ, even when that faith is not explicit?

Distinguo Sanctifiying grace is the grace freely given by God which saves us and it doesn't come in bushels or pecks

According to the Council of Trent sanctifying grace is not merely a formal cause, but "the only formal cause" (unica causa formalis) of our justification.
old catholic encyclopedia - justification

Actual Grace is the spiritual grease that tunes your soul into being better and better.  So, corporal and spiritual works of mercy are not the cause of salvation.   They help you stick to the narrow path, but they aren't the narrow path.
What I do not know, and prehaps only God knows, is what good acts of mercy do to the soul of the one who doesn't believe in Christ.


Why do Mormons use Trinitarian language in baptism when they explicitly reject Trinitarianism?

It is not the trinitarian language, it is the language with which Christ commanded his disciples to go and baptize:

  Go ye therefore, and teach all nations, baptizing them in the name of
  the Father, and of the Son, and of the Holy Ghost: (Matt 28:19)

Trinitarianism interprets this to mean one God with three personages. The fulness of the gospel defines this as the Godhead:

God the Father, who is a physical being, the father of our spirits who is all powerful.

God the Son, who was Jehovah born in the flesh as Jesus Christ, our spirit brother, the eldest of all the spirit children of the father, to whom the father gave his power to create the earth, who suffered the atonement for the salvation of men.

God the Holy Ghost, who remains a spirit, and because he is a spirit he can communicate with our spirits and testify of the truthfulness of all things.

There are three Gods in the Godhead, but this does not make the LDS tri-theist, that would suggest that they worship three gods. Latter-Day Saints only worship one God, the God that Christ worshipped; God the Father.

President Gordon B. Hinckley gave this in an address to the church about the The Father, Son, and Holy Ghost in 1998:

  Members of the Godhead Are Perfectly United

  They are distinct beings, but they are one in purpose and effort. They
  are united as one in bringing to pass the grand, divine plan for the
  salvation and exaltation of the children of God.

  In His great, moving prayer in the garden before His betrayal, Christ
  pleaded with His Father concerning the Apostles, whom He loved,
  saying:

  “Neither pray I for these alone, but for them also which shall believe
  on me through their word;

  “That they all may be one; as thou, Father, art in me, and I in thee,
  that they also may be one in us” (John 17:20–21).

  It is that perfect unity among the Father, the Son, and the Holy Ghost
  that binds these three into the oneness of the divine Godhead.


Can LDS women be Sunday School Presidents?

To preface my answer, not all Church policy is shaped by doctrine. Some policies are practical.
That said, I don't know why this is the case, but the handbook does say:

12.2.2. Ward Sunday School Presidency
Members of the ward Sunday School presidency are priesthood holders.

Also, speaking of the ward Sunday School president:

He also oversees the calling and setting apart of other Sunday School workers. He may assign his counselors to call and set them apart.

This, of course, requires the priesthood to do.


Can a non-Catholic receive Baptism (to formally marry a Catholic), without converting to the Catholic faith?

Once she receives the sacrament of Baptism, is she required to convert to Catholicism for that Baptism - and therefore the marriage - to be valid in the eyes of the Church and in the eyes of God?

First off, Baptism is pretty big deal in the Catholic Church. In order to ensure that the adult is serious and understands what it entails, they must go through the Rite of Christian Initiation of Adults (RCIA), a series of classes about the beliefs of the Catholic faith, typically taking place over several months.* At the end of that period, usually at the Easter Vigil, they publicly profess that they believe all that the Catholic Church teaches, and express their desire to join the Catholic Church. That is, they are publicly converting to Catholicism. They then receive the sacrament of Baptism, along with both the sacrament of Confirmation and their first sacrament of the Eucharist.

In other words, converting to Catholicism is a prerequisite for Baptism (and the accompanying Confirmation and Eucharist). While you could certainly lie when you publicly say that you believe all that the Catholic Church teaches and then get baptized, that would make the Baptism invalid in the eyes of the Church, as well as the consequent sacrament of marriage (even if it's never "caught" by the Church).

If your girlfriend is not prepared to leave her Buddhist faith and convert to Catholicism, then she cannot become baptized.

* Some parishes allow individuals to join RCIA if they want to become educated in the Catholic faith, but do not intend to convert or be baptized. It's not uncommon for an interfaith couple to join RCIA together so that the non-Catholic better understands their spouse's faith.

  I have read that a Catholic can even marry an unbaptized non-Catholic within the Church, but that such a marriage "would be valid, but not sacramental."

This is correct. The sacrament of marriage can only happen between two Catholics. However, non-sacramental marriage* between a Catholic and non-Catholic is permitted and valid if the proper procedure is followed. A Catholic wishing to marry a non-Christian** would need to request a "dispensation for disparity of cult". This process is described in the Catechism of the Catholic Church (CCC) sections 1633 through 1637, in particular 1635 (emphasis in the original):

  According to the law in force in the Latin Church, a mixed marriage [i.e. two Christians where only one is Catholic] needs for liceity the express permission of ecclesiastical authority. In case of disparity of cult [i.e. marrying a non-Christian] an express dispensation from this impediment is required for the validity of the marriage. This permission or dispensation presupposes that both parties know and do not exclude the essential ends and properties of marriage; and furthermore that the Catholic party confirms the obligations, which have been made known to the non-Catholic party, of preserving his or her own faith and ensuring the baptism and education of the children in the Catholic Church.

In other words, you must:

Get explicit permission from an ecclesiastical authority

This is usually the office of the Bishop of your diocese
The exact process will vary depending on your diocese, but nowadays it's typically started by talking with the priest/deacon of your parish, who then submits a form to the Bishop. Here is the form for the Diocese of Honolulu, and here is a similar form for the Diocese of Ossory.

Be in agreement with your future wife about "the essential ends and properties of marriage", as understood by the Catholic Church

The most basic of these ends and properties would be that it is a life-long monogamous union between a man and woman

As a Catholic, ensure that any children of yours are baptized and educated in the teachings of the Catholic Church

If these things are followed, then you are free to marry your girlfriend even if she chooses to remain Buddhist.

* The difference between a sacramental and non-sacramental marriage is partially described in this question. If you have further questions about the difference, it's best to ask a new question on this site.

** The process of marrying a baptized Christian of a different denomination (called a "mixed marriage") is similar, but has a few differences that are best answered in other question.

  If we were to marry in this fashion without her Baptism, is there a danger of living in mortal sin as a result? I assume if that were the case the marriage would not be allowed in the first place, but this is a grey area I would like to have clarified.

No, if you follow the process of being granted a dispensation for disparity of cult, you are not living in any sort of mortal sin (if you fail to get the dispensation, then you would be committing fornication, which is a mortal sin). Indeed, CCC 1637 encourages the Catholic to practice their faith in the hopes of leading their spouse to join the faith of their own volition.

  In marriages with disparity of cult the Catholic spouse has a particular task: "For the unbelieving husband is consecrated through his wife, and the unbelieving wife is consecrated through her husband." It is a great joy for the Christian spouse and for the Church if this "consecration" should lead to the free conversion of the other spouse to the Christian faith. Sincere married love, the humble and patient practice of the family virtues, and perseverance in prayer can prepare the non-believing spouse to accept the grace of conversion.

So the Church, rather than believing you to be in a state of mortal sin, supports your marriage (so long as the criteria above were followed) and hopes that in the future it will lead your wife to convert to Catholicism of her own free will.


How do evangelicals interpret 1 Corinthians 10:16?

From Barnes' Notes on the Bible:

  The more obvious signification is, that there is a sense in which it
  may be said that the cup is blessed, and that by prayer and praise it
  is set apart and rendered in some sense sacred to the purposes of
  religion. it cannot mean that the cup has undergone any physical
  change, or that the wine is anything but wine; but that it has been
  solemnly set apart to the service of religion, and by prayer and
  praise designated to be used for the purpose of commemorating the
  Saviour's love. That may be said to be blessed which is set apart to a
  sacred use (Genesis 2:3; Exodus 20:11); and in this sense the cup may
  be said to be blessed; see Luke 9:16, "And he took the five loaves and
  the two fishes, and looking up to heaven he blessed them," etc.;
  compare Genesis 14:9; Genesis 27:23, Genesis 27:33, Genesis 27:41;
  Genesis 28:1; Leviticus 9:22-23; 2 Samuel 6:18; 1 Kings 8:41.

  Is it not the communion of the blood of Christ? - Is it not the emblem
  by which the blood of Christ is exhibited, and the means by which our
  union through that blood is exhibited? Is it not the means by which we
  express our attachment to him as Christians; showing our union to him
  and to each other; and showing that we partake in common of the
  benefits of his blood? The main idea is, that by partaking of this cup
  they showed that they were united to him and to each other; and that
  they should regard themselves as set apart to him. We have communion
  with one κοινωνία koinōnia,) that which is in "common," that which
  pertains to all, that which evinces fellowship) when we partake
  together; when all have an equal right, and all share alike; when the
  same benefits or the same obligations are extended to all. And the
  sense here is, that Christians "partake alike" in the benefits of the
  blood of Christ; they share the same blessings; and they express this
  together, and in common, when they partake of the communion.

  The bread ... - In the communion. It shows, since we all partake of
  it. that we share alike in the benefits which are imparted by means of
  the body of the Redeemer. In like manner it is implied that if
  Christians should partake with idolaters in the feasts offered in
  honor of idols, that they would be regarded as partaking with them in
  the services of idols, or as united to them, and therefore such
  participation was improper.

(emphasis added by me)

The idea is that it is participating in the body and blood of Christ, not partaking of the body and blood of Christ in the sense that it's literally his body. The point of the passage is to say that when we eat the elements, we participate in their symbolism, their celebration of Christ, and their uniting the believers together. Therefore, similarly, if we participate in idol feasts, we're participating in the symbolism, celebration of the idol, and uniting that comes with it. It's a warning against participating in these things, not necessarily referencing its literal transformation into Christ's body.

EDIT: This is highlighted too by Paul in verses 25 and 26 where he says they can eat anything sold in the market (some of which had been sacrificed to idols) because “The earth is the Lord’s, and everything in it." Even though it had been sacrificed to idols, by buying it in the market they weren't participating in the idol worship it was originally consecrated for.


Ruling on eating pork in Christianity as per Bible?

Unlike Judaism, Christianity has no rule prohibiting (or commanding) the eating of pork. In fact, in Acts 10:9-16, Peter has a vision where a sheet is lowered from Heaven with "all sorts of animals, reptiles, and birds" on it. He is then commanded to get up, kill, and eat the animals. To this, Peter is shocked and replies that he has never eaten anything unclean (as per the Judaic Law). To this, God replies:

  Acts 10:15 (NLT)
  15 But the voice spoke again: “Do not call something unclean if God has made it clean.”

There is of course a deeper meaning, but on the surface, God is telling Peter that nothing is unclean now (that is, no animals are unclean). This includes pigs and pork, so eating bacon and the like is perfectly acceptable (and happens quite often in the United States) among Christians. Another piece of support is that the four things still considered prohibited for Christians are listed in Acts 15:

  Acts 15:29 (NLT)
  29 You must abstain from eating food offered to idols, from consuming blood or the meat of strangled animals, and from sexual immorality. If you do this, you will do well. Farewell.

None of these four actions apply to typical ways to consume pork. So, as a Christian, it is perfectly fine to eat pork.

As noted by waxeagle in a comment, not all Christians consider it acceptable to eat pork. Some sects maintain a kosher lifestyle whereas others abstain from meat entirely. However, these don't compose a significant portion of Christianity. The best course of action is to ask the Christian group you're part of.


What is the significance of the names of the 4 rivers in the Garden of Eden?

I'm not sure that there is any real profound significance.  The names do have meanings as follows:

Pishon: increase
Gihon: bursting forth
Tigris - rapid
Euphrates - fruitfulness.

One thing that may be of note is that Adam may very well have given them these names. God specifically had Adam name the animals.  This seems to be inherent in the dominion which God gave to man over all the earth.  God Himself named things in Genesis 1, calling the light "day", the darkness "night", the expanse "heaven", the dry land "earth", and the waters "seas".  (Genesis 1:5, 8, 10)  In Genesis 2, it is the man who gives names to things:

  Out of the ground the Lord God formed every beast of the field and every bird of the sky, and brought them to the man to see what he would call them; and whatever the man called a living creature, that was its name. Genesis 2:19 NASB

So, while we are not specifically told that man named the rivers, it is certainly possible.  If so, it would be another demonstration of man's dominion over the earth.

Furthermore, the very fact that specific rivers are named and described with specific details strongly suggests that the account is not merely a story but an actual historical event and that Adam was, indeed, an actual historical figure.  The genealogy of Adam to Abraham, Moses and David is similar in that fictitious characters cannot trace their lineage to real people.

If the account were, in fact, just a story of creation, the fact that one of the rivers flowed around the entire land of a certain region would be quite odd, as would be the mentioning of gold, bdellium and onyx stones being present in a particular region.  The story is written as if it were a real place where real events occurred and where people could visit if they so chose.

In conclusion, the significance would be to possibly illustrate mankind's dominion over the earth and also that the story is actually a historical event.


Matthew 11:3: Was John the Baptist losing his faith?

The Eastern Orthodox interpretation of this passage is not that John personally asked this question because his faith was wavering; but rather that he sent his own followers to ask the question (11:2) so that they would begin believing in Jesus and follow Him.

The Gospel explanations by Theophylact, an 11th century Byzantine, are perhaps the best source of concise Eastern Orthodox interpretations of the Gospels.  [Commentaries were in Greek and often point out subtleties in the Greek text that are missed in most Bible translations].  The King James translators sometimes consulted Theophylact when they encountered a difficult passage.]  Theophylact was almost always summarizing much older commentaries from the Church Fathers, especially John Chrysostom.  He comments on this passage:

    Now when John had heard in the prison the works of Christ, he sent two of his disciples, and said unto him, Art Thou He that cometh, or
    do we look for another?

  John did not ask as if he himself did not know Christ.  How could this
  be when he had borne witness to Him, saying, "Behold the Lamb of God"?
  [John 1:29].  But because his disciples were jealous of Christ, John
  sent them to acquire more evidence, so that by seeing the miracles
  they might believe that Christ is greater than John.  This is why he
  himself pretends to ask, "Art Thou He that cometh?" that is, He Whose
  coming in the flesh is awaited in the Scriptures.  Some believe that
  by saying, "He that cometh", he was asking about the descent into
  hades, as if not knowing the answer, John were questioning, "Art Thou
  He that goeth even into hades, or should we look for another?"  But
  this is foolishness, for how could John, who was greater than the
  prophets, not know of the crucifixion of Christ and the descent into
  hades, when he had called Christ the Lamb Who would be sacrificed for
  us?  John knew, therefore, that the Lord would also go down into hades
  in the soul so that even there, as St. Gregory the Theologian [Gregory
  of Nazianzus, 329-390] says, He might save those who would have
  believed if He had become incarnate in their day.  John did not ask
  this because he did not know the answer, but rather because he wanted
  to provide his disciples with the evidence of Christ's miracles.
  Look, then, how Christ answers the question ... [cf. Matthew 11:4-6]

  The Explanation of the Holy Gospel According to St. Matthew

Two questions have arisen regarding this explanation:

Why did John the Baptist needed to "pretend" instead of simply telling his disciples, "Go and look at all the miracles He performs"?
Why did Jesus asked the disciples to “go back and report to John..." (Matthew 11:4) while He knew that it was all about the John's disciples rather than John himself?

The answer to the first question lies in understanding that John's disciples were intensely loyal to him and jealous of the attention that Christ was receiving at, in their eyes, John's expense.  This is evident, John Chrysostom observes, in their earlier "complaints":

  And they came to John, and said to him, “Rabbi, he who was with you beyond the Jordan, to whom you bore witness, here he is, baptizing,
  and all are going to him.” (John 3:26)

  Then the disciples of John came to him, saying, “Why do we and the Pharisees fast, but your disciples do not fast?” (Matthew 9:14)

Jesus Himself testifies of their obstinance when, knowing their lingering doubts, he concludes his talk to them saying And blessed is he, whosoever shall not be offended in Me (Matthew 11:6).

John Chrysostom's explanation for the Baptist's feigned curiosity is that his disciples obstinance concerned him, since he would not be around much longer to guide them toward Christ.  Thus, he needed to do something that would require them to speak with Christ in person.  He writes:

  For as yet they knew not who Christ was, but imagining Jesus to be a
  mere man, but John greater than after the manner of man, were vexed at
  seeing the former held in estimation, but the latter, as he had said,
  now ceasing. And this hindered them from coming unto Him, their
  jealousy quite blocking up the access. Now so long as John was with
  them, he was exhorting them continually and instructing them, and not
  even so did he persuade them; but when he was now on the point of
  dying, he uses the more diligence: fearing as he did lest he might
  leave a foundation for bad doctrine, and they continue broken off from
  Christ. For as he was diligent even at first to bring to Christ all
  that pertained to himself; so on his failing to persuade them, now
  towards his end he does but exert the more zeal.

  Homily XXXVI on the Gospel According to St. Matthew

The second question is why did Jesus tell John's disciples to go back to him, since He would have known John's purpose in sending them.  The answer, I think, is that they were still not entirely convinced and needed additional reinforcement from their own teacher.  If the case were otherwise, Jesus would not have added And blessed is he, whosoever shall not be offended in Me.  Theophylact paraphrases Christ's words, "'Tell John what you see, and certainly he will use the opportunity to bear witness more fully to you concerning Me.'"  John Chrysostom also further explains:

  For if He had said, "I am He," both this would have offended them, as
  I have already said; and they would have thought, even if they had not
  spoken, much as the Jews said to Him, You bear record of Yourself
  [John 5:31; 8:13].

  Ibid.

 Afterword

Since answering this question, it was modified to ask for interpretations of this Scripture by "the three main branches of Christianity".

I would submit that the "Orthodox" interpretation is essentially the (or at least "an") interpretation of the first millennium Church Fathers (at least that's what the Orthodox Church strives for).

John Chrysostom is a pre-schism Church Father and continues to be recognized as a Doctor of the Roman Catholic Church.  I assume that later Roman Catholic interpretations will be in concert with his.

Most prominent Protestant commentators, to my knowledge, also respect Chrysostom's opinions.  John MacArthur, for example, calls him "perhaps the greatest preacher of the early church".

Ellicott, however, allows that John the Baptist might have himself wavered, as "week after week passed without the appearance of the kingdom as he expected it to appear."  Matthew Henry expresses hope, but no firm opinion:  "We hope that John's faith did not fail."  The Cambridge Bible for Schools and Colleges also enumerates three possible reason's for John's inquiry - (a) despondency; (b) to confirm the faith of his disciples (Chrysostom's interpretation); or (c) to force Jesus to declare Himself the Messiah -  but it does not indicate which of the three is the best interpretation.


What is known (and/or alleged) about the moral character of the 12 disciples?

I am no expert in the apostles' lives, but here are some thoughts.

It has been said that God provides His truth in earthenware vessels. That is, they are never of impeccable moral character. Judas is an obvious example, but Peter, too, sinned against Jesus in the course of His passion (by denying him three times). The difference between the two is that Peter did not run or hide from Jesus when he saw him again and received his forgiveness.  But Judas could not forgive himself nor did he seek Jesus' forgiveness.

John 21:17 NAS

  He said to him the third time, "Simon, son of John, do you love Me?" Peter was grieved because He said to him the third time, "Do you love Me?" And he said to Him, "Lord, You know all things; You know that I love You." Jesus said to him, "Tend My sheep."

As a result, Peter remained as head of the disciples, but we all know what happened to Judas.

Also, later on, we hear of Paul rebuking Peter, apparently over his recalcitrance to eat with Gentiles. So there is still fraternal correction going on even among the apostles.

Galatians 2:11-14 NAS

  But when Cephas came to Antioch, I opposed him to his face, because he stood condemned. For prior to the coming of certain men from James, he used to eat with the Gentiles; but when they came, he began to withdraw and hold himself aloof, fearing the party of the circumcision.The rest of the Jews joined him in hypocrisy, with the result that even Barnabas was carried away by their hypocrisy. But when I saw that they were not straightforward about the truth of the gospel, I said to Cephas in the presence of all, "If you, being a Jew, live like the Gentiles and not like the Jews, how is it that you compel the Gentiles to live like Jews?

We know that the apostles all, except John, died a martyr's death spreading the kingdom. So whatever other faults they may have had, they were at least loyal.