Why were ousia and hypostasis synonymous in the Nicene Creed?

This response has been extracted from a longer article of mine on the subject (linked at the end) , hence the discontinuous numbering of its sections.
1. Ousía in Greek philosophical discourse
Deriving then from the verb "to be", as we can see in [4] ousía enters the Greek philosophical discourse with Plato, who uses it to mean the primary, fundamental kind of being, ("prōtē ousíā", pl. "prôtai ousíai"), with Aristotle afterwards using it with the same meaning. It is crucial to note that, for both Plato and Aristotle, ousía does not enter the discourse as a definition but as a question to be answered: what is the primary, fundamental kind of being? What is prōtē ousíā?
While ousía means the same for both Plato and Aristotle as a question, they provide completely different answers to that question. Plato's answer is well known: the Form, which exists in a transcendent world of Forms, is prōtē ousíā, the primary, real being, of which the particular objects in the sensible world are just shadows. Against this Platonic background, Aristotle then provides his own answer in two works, Categories and Metaphysics, in which, notably, he provides different answers.
Categories, part 5 [6]

Primary ousía is the individual, particular, concrete entity, of which species and accidents can be predicated without it being predicable of or attributable to anything else. This is actually stated in negative terms: “what is neither in a subject nor said of a subject”, i.e. the particular subject itself or "hypokeimenon" [7], literally “that which underlies or lies beneath” the universals (first of all species and genus) in which it falls and the accidents which inhere in it.

Secondary ousía ("deutérā ousíā", pl. "deúterai ousíai") is the species (first of all) and the genus to which the particular subject belongs.

Metaphysics, book VII/Zeta [8]

Primary ousía is the essence of the particular entity, which is its form, while the particular entity, the composite of form and matter, is ousía in a derivative sense. (The Aristotelian expression that the Latins translated as "essentia" is "to ti ên einai", "the what it was to be", although sometimes he uses the shorter expression "to ti esti", "the what it is".)

Species and genus are not ousía.

A question arises at this point: Is for Aristotle the form of a particular entity a particular or a universal? This, in conjunction with his statement in Z.13 that no universal is ousía, is the most disputed issue regarding Aristotle's Metaphysics, and has given rise to a whole field of Aristotelian exegesis, in which the main lines are [9] [10]:

Forms are not universal, and each particular entity has its own form which resides in that entity, so that all individuals of a given species have forms which are identical to one another but numerically different.

Forms are universal, and Z.13 actually does not exclude them as ousía.

Since the second line is basically a reversion to Platonism, IMO it is extremely implausible that it may reflect Aristotle's personal position.
Summarizing the answers that Aristotle gives to the question "What is primary ousía?":

Categories: the particular entity or "hypokeimenon", the subject which underlies all predicates and cannot be predicated of anything else.

Metaphysics: the essence of the particular entity, which is its form, which may be understood in a particular or a universal sense.

2. Hypostasis, the original cognate of substantia
Etymologically [1] [2],
hypostasis = hypó ("under") + stásis ("a standing" = (hístēmi ("to stand") + -sis, verbal noun suffix)) = "that which stands under"
is a direct cognate of [3] [4] [5] [6]:
substantia = sub ("under") + stans ("standing", present active participle of stō ("stand")) = "that which stands under".
According to [7], the first recorded use of hypostasis as "substance" was in the book "On the cause of plants" by Aristotle's successor Theophrastus (c. 371 - c. 287 BC), while the term may have been introduced in the philosophical discourse either by the Stoic Poseidonius (c. 135 BC - c. 51 BC) according to some, or by the Epicurean Demetrius Lacon (fl. late 2nd century BC) according to others, in both cases with the meaning of objective or concrete existence or reality. Thus, real entities were said to "have hypostasis", whereas merely apparent or imaginary entities did not.
Recalling at this point that both the Stoic and the Epicurean philosophical schools were materialistic, the first conceiving the all-pervading Logos as a subtle fiery aether and the second conceiving reality as consisting just of atoms and void, it is clear that, to the extent that they used the term ousía, they would not have used it in the sense of form understood as universal or even in the sense of form at all, but in the sense of the individual, particular, concrete entity, the "hypokeimenon", “that which underlies or lies beneath”, which clearly overlaps with the meaning of hypostasis. Therefore, it is clear that for both Stoics and Epicureans the terms ousía and hypostasis were synonyms, but that was due to the specific sense in which both schools understood ousía.
Introducing now the Latins, who were now becoming interested in philosophy, into the picture:
Since, per linguistic design, substantia = hypostasis,
and, per Stoic and Epicurean understanding of ousía, hypostasis = ousía,
then, for the Latin-speaking Stoic- and Epicurean-dominated culture, substantia = ousía.
This was precisely the case of Tertullian, who was heavily influenced by Stoic metaphysics and coined the formula "tres Personae, una Substantia" early in the III century, after which substantia came to mean, among Latin-speaking Christians, the single infinite spirit that the Father, the Son and the Holy Spirit have in common, which is the meaning of ousía in the Nicene sense, as we will see next.
5. The "one ousía" answer to Arianism, its modalistic and tritheistic risks, and Nicaea's "one hypostasis" as prevention of the second.
Since Arians denied that the Son and the Father were one, they had to interpret Jesus' words "I and the Father are one." (Jn 10:30) in the sense of only moral oneness and not ontological oneness. To counter that eisegesis, the orthodox sought for the right word to add to Jn 10:30 to convey unequivocally the sense of ontological oneness: "I and the Father are one"... what?
We arrive at the same question from four key statements by Jesus of his divinity that were not mentioned in the previous section: the 4 times in which He explicitely applied to Himself the divine Name in the first person revealed in Ex 3:14: "Ehyeh", "Ego Eimí", I Am": Jn 8:24,28,58 & 13:19. If each of the Father and the Son names Himself "Ego Eimí", "I Am", then Each is a distinct "I" but Both are the same... what?
The natural answer to that question was the term ousía, which derived precisely from the verb "eimí", "to be". So, the initial orthodox answer to the Arian challenge was: the Father and the Son are one ousía and two prósōpa, one being and two persons. Now, each term in that answer, ousía and prósōpon, was at risk of misinterpretation resulting in another heresy.
The risk of misinterpretation of ousía came from the fact that the philosophical stage at the beginning of the IV century was very different from that of around 70 AD when the Letter to the Hebrews was written. Platonism had come back with Plotinus (204-270) and Porphyry (234-305), and with it the notions of forms and universals and therefore the issue of the exact meaning of ousía. Let us recall from section 1 that ousía had entered the philosophical discourse, some 700 years before Nicaea, not as a definition but as a question to be answered, and for which Aristotle had provided two different answers, one in the Categories and another in the Metaphysics, the second of which could in turn be interpreted in two different ways:
C: the individual, particular, concrete subject or "hypokeimenon", “that which underlies or lies beneath”;
M1: the essence or form, understood as particular;
M2: the essence or form, understood as universal.
Each of these senses of ousía led to a different sense of the statement that the Father and the Son were "homoousious", "of the same ousía":
C: They were the same particular, concrete subject.
M1: They had the same essence or form, understood as particular.
M2: They had the same essence or form, understood as universal.
It is easy to see that, while sense C amounts to modalism, sense M2 amounts to tritheism, since the case would be the same as stating that three horses have the same essence or form. It was probably to prevent the risk of understanding ousía as a universal of which there were multiple instances, or equivalently, of understanding the expression "of the same ousía" in the sense of only qualitative identity instead of numerical identity, that the Nicaea fathers added hypostasis - which, as we saw in section 2, had the meaning of objective or concrete existence or reality - as synonym of ousía, anathematizing those who asserted that the Son of God "is of another hypostasis or ousía" [1] [2]. Since substantia was originally the cognate and equivalent of hypostasis, making hypostasis equivalent to ousía (M1) reinforced the Western understanding of substantia as the Latin equivalent of ousía (M1) that had begun with Tertullian.
Whereas the addition of hypostasis as synonym of ousía effectively prevented the M2 sense of ousía as universal, which leads to tritheism, it in effect promoted the C sense - which is evident from the etymological equivalence of hypostasis, literally "that which stands under", with hypokeimenon - which leads to modalism.
Which takes us precisely to the risk of misinterpretation of prósōpon, which came from the fact that it meant "face", "mask" or "character in a theatrical play" [3]. Thus modalists could claim that they were in complete agreement with the definition of Nicaea.
6. The three Hypostases formula: appearance, toleration by St. Athanasius and resistance by St. Jerome.
As noted in section 3, the use of hypostasis as synonym of ousía, so that the Father and the Son were said to be "of the same hypostasis", was inconsistent with the sense of hypostasis in Heb 1:3, since that passage necessarily implies - from the very notion of "charaktēr" as impressed image or copy, reproduction, representation - that the Son is or has a numerically different hypostasis from that of the Father, irrespective of what hypostasis may mean.
It was not this consideration, however, what motivated orthodox theologians to advocate formulating trinitarian doctrine in terms of three hypostases, but the realization that using all the terms that can convey a sense of objective reality - i.e. hypostasis and ousía - to denote the common being of the Father and the Son amounted to leaving the door open for modalists to claim that they were in full agreement with the dogmatic definitions of the Church.
The notion of three Hypostases had been introduced in Christian theology by Origen and had been used also by his former student St. Dionysius of Alexandria. Its first documented use after Nicaea was by (also Alexandrian) St. Athanasius, in his work "In Illud Omnia", written probably c. 335 [1] [2]:
"For the fact of those venerable living creatures [Isa 6:3; Rev 4:8] offering their praises three times, saying 'Holy, Holy, Holy,' proves that the three Hypostases are perfect, just as in saying 'Lord,' they declare the one Ousía."
After that, the expression was not used again by St. Athanasius, in deference to the anathema of Nicaea [1], but was used by non-Nicene bishops, e.g. in the Dedication creed of the council of Antioch of 341 and in a letter by the homoiousian bishop George of Laodicea in 359. But by the time of the Council of Alexandria of 362, presided by St. Athanasius, the expression was already being used by people holding homoousian orthodoxy, as attested by the letter to the Church in Antioch written by that Council, known as "Tomus ad Antiochenos" [3] [4], which acknowledged that both expressions, "three hypostases" and "one hypostasis", could used in a sense consistent with homoousian orthodoxy.
In stark contrast with St. Athanasius in the Council of Alexandria of 362, St. Jerome, in his epistle 15 to Pope St. Damasus, written in 376 or 377 [5] [6] [7], manifests his deep trouble with the use of the formula "three hypostases".
7. The three Hypostases formula: proposal by St. Basil and St. Gregory of Nyssa and increasingly official Church adoption since 382.
After Nicaea, the first orthodox theologian to propose a notion of hypostasis distinct from that of ousía in a published work was St. Basil of Caesarea (330-379), and he does it in his epistles 214 (375) to Count Terentius [1] and 236 (376) to Amphilochius [2]. In both letters, the main motive for using hypostasis as synonym of Person is that, if the orthodox keep speaking of one hypostasis, they set the stage for the Arians to accuse them of Sabellianism (modalism).
St. Gregory of Nyssa (335-394) devotes his epistle 35 (c. 380) addressed to his brother Peter - which is often referred to as St. Basil's epistle 38 to his brother Gregory - to the difference between ousía and hypostasis. St. Gregory starts by distinguishing between the common or general and the particular, and provides a definition of hypostasis [3].
In 381, i.e. around one year after Gregory's letter to Peter, the second Ecumenical Council convened in Constantinople, and the next year, i.e 382, a synod of bishops assembled in that city and sent a Synodical Letter to Pope Damasus and other Western bishops, which is the first official (though not ecumenical) Church document speaking of three Hypostases [4]:
Letter from the Constantinople Synod of 382 to Pope Damasus
What we have undergone — persecutions, afflictions, imperial threats, cruelty from officials, and whatever other trial at the hands of heretics — we have put up with for the sake of the gospel faith established by the 318 fathers at Nicaea in Bithynia. You, we and all who are not bent on subverting the word of the true faith should give this creed our approval. It is the most ancient and is consistent with our baptism. It tells us how to believe in the name of the Father and of the Son and of the Holy Spirit: believing also, of course, that the Father, the Son and the Holy Spirit have a single Godhead and power and substance, a dignity deserving the same honour and a co-eternal sovereignty, in three most perfect Hypostases, or three perfect Persons. So there is no place for Sabellius’s diseased theory in which the hypostases are confused and thus their proper characteristics destroyed.
End of quote from the Constantinople Synod of 382.
In 431 the third Ecumenical Council convened in Ephesus. The third letter of St. Cyril of Alexandria to Nestorius, which was read at the council and included in the proceedings, spoke of the Hypostases of the Word and of the Holy Spirit [5]:
St. Cyril of Alexandria, in his 3rd letter to Nestorius
All the expressions, therefore, that occur in the gospels are to be referred to one Person, the one enfleshed Hypostasis of the Word.
For even though the Spirit exists in his own Hypostasis and is thought of on his own, as being Spirit and not as Son, even so He is not alien to the Son.
End of quote from St. Cyril.
In 451 the fourth Ecumenical Council convened in Chalcedon and proclaimed a Christological definition which contains all the terms considered so far: ousía, prosopon, hypostasis, and nature [6] [7].
Finally, in 553 the fifth Ecumenical Council convened in Constantinople and proclaimed a series of trinitarian and Christological definitions, the first of which explicitely identifies ousía with physis and hypostasis with prosopon [7].
References
Section 1
[4] https://en.wiktionary.org/wiki/%CE%BF%E1%BD%90%CF%83%CE%AF%CE%B1
[5] https://en.wiktionary.org/wiki/%CE%BF%CF%85%CF%83%CE%AF%CE%B1
[6] Studtmann, Paul, "Aristotle's Categories", The Stanford Encyclopedia of Philosophy (Fall 2017 Edition), Edward N. Zalta (ed.)
https://plato.stanford.edu/archives/fall2017/entries/aristotle-categories/
[7] https://en.wiktionary.org/wiki/hupokeimenon
[8] Cohen, S. Marc, "Aristotle's Metaphysics", The Stanford Encyclopedia of Philosophy (Winter 2016 Edition), Edward N. Zalta (ed.)
https://plato.stanford.edu/archives/win2016/entries/aristotle-metaphysics/
[9] Loux, Michael J., "Primary Ousia: an essay on Aristotle's Metaphysics Z and H", Cornell University Press, 2008.
https://books.google.com/books?id=1DOIpuLnrnIC
[10] Cohen, S. Marc, "Z.13: Substances and Universals", 2008.
https://faculty.washington.edu/smcohen/433/Z13Lecture.pdf
Section 2
[1] https://en.wiktionary.org/wiki/%E1%BD%91%CF%80%CF%8C
[2] https://en.wiktionary.org/wiki/%CF%83%CF%84%CE%AC%CF%83%CE%B9%CF%82
[3] https://en.wiktionary.org/wiki/substantia
[4] https://en.wiktionary.org/wiki/sub#Latin
[5] https://en.wiktionary.org/wiki/stans#Latin
[6] https://en.wiktionary.org/wiki/sto#Latin
[7] Ute Possekel, "Evidence of Greek philosophical concepts in the writings of Ephrem the Syrian", Peeters Publishers, Louvain, 1999.
https://books.google.com/books?id=rZ3gGQuJUS4C
Section 5
[1] http://www.earlychurchtexts.com/public/creed_of_nicaea_325.htm
[2] http://www.fourthcentury.com/urkunde-24/
[3] https://en.wiktionary.org/wiki/%CF%80%CF%81%CF%8C%CF%83%CF%89%CF%80%CE%BF%CE%BD
Section 6
[1] Thomas G. Weinandy, Athanasius: A Theological Introduction, Ashgate Publishing, 2007.
https://books.google.com/books?id=SGOpA_MjSUgC
[2] https://www.elpenor.org/athanasius/in-illud-omnia.asp?pg=7
[3] Lewis Ayres, Nicaea and Its Legacy: An Approach to Fourth-Century Trinitarian Theology, Oxford University Press, Oxford, Oct 28, 2004.
https://books.google.com/books?id=iT4VDAAAQBAJ
[4] http://www.newadvent.org/fathers/2818.htm
[5] The Letters of Saint Jerome, Aeterna Press, 2016.
https://books.google.com/books?id=iTwIDAAAQBAJ
[6] http://www.newadvent.org/fathers/3001015.htm
[7] http://www.earlychurchtexts.com/main/jerome/jerome_ep_15_tres_hypostases.shtml
For the quoted passage, I used this Latin text to improve the accuracy of the English translation in the previous two references.
Section 7
[1] https://www.elpenor.org/basil/letters-3.asp
[2] https://www.elpenor.org/basil/letters-3.asp?pg=39
[3] https://www.scribd.com/document/212698195/Letter-35
[4] http://www.papalencyclicals.net/councils/ecum02.htm
[5] http://www.papalencyclicals.net/councils/ecum03.htm
[6] Richard Price and Michael Gaddis, The acts of the Council of Chalcedon, Liverpool University Press, 2005.
https://books.google.com/books?id=6IUaOOT1G3UC
[7] Pavouris, Raphael (2001), The condemnation of the Christology of the three chapters in its historical and doctrinal context: the assessment and judgement of Emperor Justinian and the Fifth Ecumenical Council (553). PhD thesis, University of Glasgow.
http://theses.gla.ac.uk/1503/
Article from which the above has been extracted:
http://ousiakaihypostasis.blogspot.com


Why did "Lift Every Voice and Sing" become the "Black National Anthem"?

"Lift Every Voice and Sing" was written as a poem by James Weldon Johnson for a celebration of Abraham Lincoln’s birthday in 1900. In the early 1900's, singing this song became a way for African Americans to demonstrate their patriotism and hope for the future. In calling for earth and heaven to "ring with the harmonies of Liberty," they could speak out subtly against racism and Jim Crow laws—and especially the huge number of lynchings accompanying the rise of the Ku Klux Klan at the turn of the century. In 1919, the NAACP adopted the song as "The Negro National Anthem." By the 1920s, copies of "Lift Every Voice and Sing" could be found in black, often Baptist, churches across the country.

In the 1970's, this song experienced a revival with the Civil Rights Movement.

It resonates strongly as a Christian hymn because it is a song about exodus. It is a story of a journey sanctified by faith, and protected and prospered by God.  For African Americans, the civil rights movement was their exodus story. Segregation, disenfranchisement, and racism were their Egypt, and this song was inspiration for the journey.

Bearden, Romare and Henderson, Harry. A History of African-American Artists (From 1792 to the Present), pp. 168-180, Pantheon Books (Random House), 1993, ISBN 0-394-57016-2


What reasons do Catholics have for believing Jesus is God?

Right expectation of reason & practical use of the Trinity
Aquinas's 5 ways is like a lens for reason to apprehend God as much as we are allowed to see with our reason alone.  The Chesterton's essay you mentioned is a great defense of Catholicism as a collective mind guarding the truth, which goes beyond reason to produce wisdom for believers, which he likened to a map of the maze, to navigate our way to the Truth in the midst of confusing half-truths and half-religions offered by the world.  If you trust Chesterton's presentation of Catholicism, isn't it reasonable to learn what Catholicism has to say on the divinity of Jesus, starting with her exegesis of the New Testament, her preservation and elucidation of the Patristic writings, and her deliberations and documents issued through the historical councils?  (The third section of my answer provides a rough outline)
From your question, it looks like your predicament is to make revelation fit to reason as a prerequisite to belief.  This is something that Chesterton himself has written about (specifically Chapter 2 "The Maniac" of his apologetic book Orthodoxy), and can result in madness because mad people try to fit things that are too big into a neat system (see the topic revisited here).  Chesterton values reason and logic, but he knows their limits.  St. Thomas Aquinas also knows the limits of reason although he expanded the field that can be known by reason so wide that even the modern philosophers shrunk in fear from it, cowardly narrowing the area that they say can be known by reason!  Therefore, not only modern philosophers try to fit God into their systems, they even narrow the capabilities of reason before they do that!  Double madness, in my opinion.
While I agree with you that "there is compelling natural argument for the existence of creator-god", the same cannot be expected to discover the loving, just, and merciful character of God the Father, let alone the divinity of Jesus.  It has to come via revelation, but it can still be apprehended by reasonable faith.  We can use reason to assess the recorded testimonies of the revelation (NT writings plus the apostolic tradition) to re-present Jesus to us today, but accepting the claims of Jesus needs more than reason.  For instance, a lot of people who came across Jesus face to face and who witnessed His miracles while He was still on earth (i.e. revelation in person) did not accept Jesus's claims to be God, most notably some of the Pharisees.  Today, proper reading of the New Testament plus the testimony of the Holy Spirit in our hearts replace the face-to-face benefit that people in Jesus's own time had.
Catholicism, just like mainline Christian denominations, is very practical.  We are beings in need, God is the only supplier.  We don't need to completely understand the ingredients of spiritual food, we just eat and drink (as in communion).  Let God be God, and let human be human, who doesn't need to understand God completely to "use" Him.  We are like children who eat what our parents gave us when we were kids.
Similarly, we don't need to fit Trinity to reason, we just use the best definitions that the councils have produced.  I'm in software development; I don't need to understand how compilers and OS kernel works (although I can, since I have the training in Computer Science) but why bother?  I just read the documentation on how to use the compiler and how to call the kernel system call APIs.  It's a matter of trust (faith).  Do I trust the documentation to represent faithfully the compiler / OS Kernel?  Do I trust this compiler not to mess up my input?  Do I trust that this OS kernel has not had rootkit in it to turn my program into a booby trap that can extort people for money?  With good reason, I trust Microsoft Visual Studio 2019 and Microsoft Windows 10 Operating System.  (Some Linux die hard will think I'm mad :-) )
So Catholics trust Chesterton's map of the maze to find true north, and it's by using Catholic-produced Trinitarian understanding of God, Jesus, and the Holy Spirit.  From practical standpoint it's quite straightforward, and the data (the input) to the doctrine of Trinity is easy to understand (by reading the Bible carefully):

Jesus as prophet revealed God the Father to us, including His plan of the New Covenant.  He spent quality face to face time (about 3 years) with the 1st generation apostles teaching them many things, demonstrating miracles which only God the Father can produce as authentication.  His resurrection and subsequent appearance to the 1st generation apostles was the clincher and proof that He was a true prophet.
Jesus also claimed He was the only begotten Son of God the Father, making Him equal to God the Father.  John the Baptist (another prophet) was one of the witness when heaven opened and God the Father Himself testified that Jesus was His Son (see Matt 3:17).
When Jesus ascended back to the Heaven from where He came, He sent his Holy Spirit so He can still be with the believers entrusted to Him by the Father, but in a better way: closer to our hearts, and can be in many places at the same time (not limited to a single body while Jesus was still on earth).  Of course, because Holy Spirit is Jesus's spirit, and also God the Father's spirit, the Holy Spirit is also Divine.

Catholic Catechism paragraphs 1996-1999 is a good illustration how the Trinity is critical for our salvation:

1996 Our justification comes from the grace of God. Grace is favor, the free and undeserved help that God gives us to respond to his call to become children of God, adoptive sons, partakers of the divine nature and of eternal life.
1997 Grace is a participation in the life of God. It introduces us into the intimacy of Trinitarian life: by Baptism the Christian participates in the grace of Christ, the Head of his Body. As an "adopted son" he can henceforth call God "Father," in union with the only Son. He receives the life of the Spirit who breathes charity into him and who forms the Church.
1998 This vocation to eternal life is supernatural. It depends entirely on God's gratuitous initiative, for he alone can reveal and give himself. It surpasses the power of human intellect and will, as that of every other creature.
1999 The grace of Christ is the gratuitous gift that God makes to us of his own life, infused by the Holy Spirit into our soul to heal it of sin and to sanctify it. It is the sanctifying or deifying grace received in Baptism. It is in us the source of the work of sanctification:

Therefore if any one is in Christ, he is a new creation; the old has passed away, behold, the new has come. All this is from God, who through Christ reconciled us to himself. [2 Cor 5:17-18]

And that's all there is to it to "use" Trinity in our faith life.  It's a matter of trust (similar to my trust in Microsoft products) which leads to practical actions: what do we do about it?  The Good News demands a response.  For what it's worth, in the next section I'll share my personal response, which is rather typical of many Christians, while trying to address why I believe Jesus is God, not just prophet / wise man.
A reason to believe Jesus is God (not just prophet / wise man)
You wrote:

I think this is both a really good answer and it also doesn't answer the thing I am trying to point at -- why? Why would someone who doesn't believe this choose to instead believe it?
I do not believe in Jesus or God in the way Christians do, no. That is why I'm asking the question. Catholicism has taught me a lot and I respect the Church's teachings, but this belief (among others) stands out as a difficult one to accept. I'm wondering why other people have chosen to believe it. I'm not asking for proof like one might prove 2+2=4 (it's not that sort of question); I'm asking for reasons.

If I may take your comment lightheartedly it sounds like you're a customer who would like the seller of the Christian doctrine to convince you into buying the product "Jesus is God" rather buying other seller's product "Jesus is just a prophet" or even another product "Jesus is just a wise man".  And you want to hear customer testimonials why "Jesus is God" product works better for them so thereby giving you reasons to consider before buying.  Fair enough.  I respect that approach, and I would think Jesus Himself would have approved potential buyers to count the cost first before following Him.
I chose my screenname GratefulDisciple to reflect that I'm grateful to God that He has extended an invitation to me to be a "proud owner" of the product.  It's a badge of honor to be a disciple of Jesus, but as you can see in the "count the cost" link above, it's a product that "owns you" instead, so God (through Jesus & the Holy Spirit) can "fully manage" your life and shepherd you into eternal life.
Why would you buy a product that owns you?  If you are in IT (like I do), you know it's the cloud era.  "Managed product" (aka software as a service) is the mantra.  You no longer own a software, not even a hardware.  It's like leasing a car.  You pay a monthly amount, no worries.  Accident?  Insurance takes care of it.  Mechanical issue?  Take it to the dealer.  Want a newer model?  Start a new lease period.  Your experience is better and better, and you are very productive, as long as you keep paying and you are okay with not owning the product.  Signing your life off to Jesus is the same way.  You give up control in exchange for total protection and total happiness (although not the kind of happiness that the world offers).
If Jesus were just a prophet or a wise man, I would not be getting total protection from Him.  A prophet is someone who says and/or shows something true about God, which may or may not be previously hidden.  A wise man is someone who teaches the way to success by explaining principles of life that are hard to obtain, the way master teacher trains an apprentice over many years.  Jesus was a prophet because He revealed the new covenant to us, i.e. the invitation to become children of God.  Jesus was also a wise man who taught that the way to eternal life (success) was by obeying the new covenant commandments, just like in the OT the way to God's blessing was by obeying the Torah.
But without Him being God as well, there was no new covenant and no total protection since being inducted into the new covenant involves buying into His identity as the Son of God and accepting all the consequences (like Jesus managing your life).  Or in Christian-speak, calling Jesus your Lord (a.k.a your #1 Boss) in exchange for a protection "contract" in which He is willing to die for you FIRSTLY to "buy you out" from the devil, SECONDLY to protect you from subsequent Satan's attacks who tries to get you back through temptations, and FINALLY to represent you as your attorney + bail-money on the Day of Judgment.  A mere prophet or wise man cannot give you that service.
Catholics' defense of the Divinity of Jesus across 2,000 years
The true nature of Jesus as 100% human and 100% God was clear to the 1st generation apostles and is still clear to us from the canonized 27 New Testament writings alone.  A good example of how the New Testament alone can show the divinity of Jesus can be read via an article by a well known Catholic apologist Tim Staples on how to answer Jehovah's Witness who does not believe Jesus is God and who does not believe in the authority other than the Bible text.
But in response to various heresies which developed in the first 400 years or so, the still united Catholic church had to clarify this teaching through several definitive councils, notably the Council of Nicaea (AD 325), the Council of Chalcedon (AD 451), and several church councils in between.  The article Jesus Christ, True God and True Man from Opus Dei, a Catholic spiritual formation organization, provides a good historical development of the doctrine.
In addition, early church fathers also wrote about the Divinity of Jesus, usually in their apologetic works.  Some quotes from individual church fathers can be read in a Catholic tract the Divinity of Christ.
St. Augustine of Hippo who wrote between AD 368 and AD 430, focused on combating the Manicheans, the Donatists, the Pelagians, and the Arians.  Only his writings against the Arians had to do with the true nature of Jesus, which is part of the larger effort outlined in the Opus Dei article above.  So his task was of refining rather than defending the Divinity of Jesus, which was already uncontested since he lived post-Nicaea.
St. Thomas of Aquinas who wrote between AD 1256 and AD 1273 was in another era altogether (High Middle Ages).  He no longer had to defend the Divinity of Jesus, but rather Christianity as a whole against Islam and also to reconcile the renaissance of Aristotelian philosophy (came via the Moslem scholars) with the Neoplatonic philosophy inherent in St. Augustine's theology, which made him famous as the most successful Catholic Doctor of the Church who was able to strike the right balance between Reason and Faith via his own adaptation of Aristotelian philosophy while maintaining orthodoxy in recasting Church Fathers teachings (including St. Augustine) in Aristotelian terms.
The Stanford Encyclopedia of Philosophy has a more formal treatment of the History of the Trinitarian Doctrines which includes quotes from St. Augustine and St. Thomas Aquinas but this is more of a philosophical analysis of the various conceptions of the Trinity rather than why Catholics believe Jesus is God.  That is an excellent resource to show what reason can do with the doctrine of Trinity, and complexity-wise, it's on par with Aquinas's 5 ways.  But does it help to accept the claim that Jesus is divine?  I don't think so.
Jumping to the past 100 years, the Divinity of Jesus was under fresh attack by liberal theologians of all stripes (Catholic / Protestant leanings), philosophers, and various projects undermining the reliability of the New Testament.  In defending the faith, Catholic and Protestant scholars often join forces, quoting each other in their scholarly books such as the 3 volume Jesus of Nazareth by Pope Benedict XVI (published AD 2007, 2011, 2012) and Jesus and the Victory of God by N.T. Wright (published AD 1996).  The Catholic church documents in this era were more of relevancy of Jesus to the Faithful such as

Jesus as the incarnation of Mercy (Dives in Misericordia, AD 1980)

Jesus as the incarnate love of God (Deus Caritas Est, AD 2005)

Of course I cannot leave out the Catholic Catechism which teaches Jesus as the Son of God in Chapter 2, Article 2.


How real is Matthew 4:1-2 in terms of physical realities?

It is humanly possible to fast food for 40 days, though it is generally recommended to be very cautious about making such a decision due to the pressure it will put on your body's health and fitness. That said, several Christian teachers and writers both past and present recommend and teach about the benefits of 40-day fasting as a way to draw closer to God.

It's also noted that Christianity traditionally marks the 40 days of Lent as a period of fasting. While we find that some denominations ease the requirements (or make it purely optional), it can be expected that in earlier times 'pure' fasting would have taken place much more commonly especially within the Catholic church.

Given the above, one can expect it to have been very physically possible for Jesus to have fasted for 40 days, though doubtful that it would have been an easy, enjoyable experience!!


Why do many orthodox pastors grow long hair?
I have noticed this even with Eastern Rite Catholic priests.
Igumen Luke explains it as follows:

Orthodox Christian piety begins in the Holy Tradition of the Old Testament. Our relationship to the Lord God, holiness, worship, and morality was formed in the ancient times of the Bible. At the time of the foundation of the priesthood the Lord gave the following commandments to the priests during periods of mourning, And ye shall not shave your head for the dead [a pagan practice] with a baldness on the top; and they shall not shave their beard... (Lev. 21:5), and to all men in general, Ye shall not make a round cutting of the hair of your head, nor disfigure your beard (Lev. 19:27). The significance of these commandments is to illustrate that the clergy are to devote themselves completely to serving the Lord. Laymen as well are called to a similar service though without the priestly functions. This out ward appearance as a commandment was repeated in the law given to the Nazarene, a razor shall not come upon his head, until the days be fulfilled which he vowed to the Lord: he shall be holy, cherishing the long hair of the head all the days of his vow to the Lord... (Numbers 6:5-6).
The significance of the Nazarene vow was a sign of God's power resting on the person who made it. To cut off the hair meant to cut off God's power as in the example of Samson (see Judges 16:17-19). The strength of these pious observances, transmitted to the New Testament Church, were observed without question till our present times of willfulness and the apostasy resulting from it. Why, one might ask, do those Orthodox clergymen, while rejecting the above pious ordinances about hair, continue to observe the custom of granting various head coverings to clergy, a practice which also has its roots in the ancient ordinances of the Old Testament (cf. Ex. 24:4-6) and the tradition of the early Church (see Fusebius and Epiphanius of Cyprus concerning the miters worn by the Apostles John and James)?
The Apostle Paul himself wore his hair long as we can conclude from the following passage where it is mentioned that "head bands," and "towels" touched to his body were placed on the sick to heal them. The "head bands" indicate the length of his hair (in accor dance with pious custom) which had to be tied back in order to keep it in place (cf. Acts 19:12). The historian Egezit writes that the Apostle James, the head of the church in Jerusalem, never cut his hair (Christian Reading, Feb. 1898, p.142, [in Russian]).
If the pious practice among clergy and laity in the Christian community was to follow the example of the Old Testament, how then are we to understand the words of Saint Paul to the Corinthians cited earlier (I Cor. 11:14)? Saint Paul in the cited passage is addressing men and woman who are praying (cf. I Cor. 11:3-4). His words in the above passages, as well as in other passages concerning head coverings (cf. I Cor. 11: 4-7), are directed to laymen, not clergy. In other passages Saint Paul makes an obvious distinction between the clerical and lay rank (cf. I Cor. 4:1, I Tim. 4:6, Col. 1:7, and others). He did not oppose the Old Testament ordinance in regard to hair and beards since, as we have noted above, he himself observed it, as did Our Lord Himself, Who is depicted on all occasions with long hair and beard as the Great High Priest of the new Christian priest hood.
In our passage noted previously, Both not even nature itself teach you, that, if a man have long hair, it is a shame unto him? (I Cor. 11:14) Saint Paul uses the Greek word for "hair." This particular word for hair designates hair as an a ornament (the notion of length being only secondary and suggested), differing from [Gr.] thrix (the anatomical or physical term for hair). Saint Paul's selection of words emphasizes his criticism of laymen wearing their hair in a stylized fashion, which was contrary to pious Jewish and Christian love of modesty. We note the same approach to hair as that of Saint Paul in the 96th canon of the Sixth Ecumenical Council where it states: "Those therefore who adorn and arrange their hair to the detri ment of those who see them, that is by cunningly devised intertwinings, and by this means put a bait in the way of unstable souls."
In another source, The Eerdmans Bible Dictionary, we read the follow ing concerning the Old Testament practice: "To an extent, hair style was a matter of fashion, at least among the upper classes, who were particularly open to foreign [pagan] influence. Nevertheless, long hair appears to have been the rule among the Hebrews (cf. Ezek. 8:3), both men and women" (cf. Cant 4:1; 7:5). Thus we observe that cropped or stylized hair was the fashion among the pagans and not acceptable, especially among the Christian clergy from most ancient times up to our contemporary break with Holy Tradition. It is interesting to note that the fashion of cropped or stylized hair and shaved beards found its way into the Roman Catholic and Protestant worlds. So important had this pagan custom be come for Roman clergy by the 11th Century that it was listed among the reasons for the Anathema pronounced by Cardinal Humbert on July 15, 1054 against Patriarch Michael in Constantinople which precipitated the Western Church's final falling away from the Orthodox Church: "While wearing beards and long hair you [Eastern Orthodox] reject the bond of brotherhood with the Roman clergy, since they shave and cut their hair." -Concerning the Tradition of Long Hair Beards

St. Tikhon of Moscow
Custom of wearing long hair and beards is not universal nowadays.
Here is what the St. Tikhon of Moscow has to say on the subject matter:

St. Tikhon and Clerical Appearance
When Patriarch St. Tikhon was Bishop in America early this century, he ordered his clergy to shave and wear Western clerical dress. What does this say of your "traditional" dress?
We have seen only one directive attributed to St. Tikhon on this subject, and it by no means "orders" clergy in America under his jurisdiction to abandon traditional Orthodox dress and grooming. It is also well known that the late Father Georges Florovsky disputed the authenticity of this directive. Whatever the case, St. Tikhon did openly speak of a distinction between the "essentials" and "accidentals" of the Faith, allowing for a number of innovations, including some in clerical appearance. A distinction of the kind made by the Saint is atypical in Orthodoxy, wherein "externals" (matters of apparent accident) are thought to reflect and to be inseparable from an "internal" (or essential) reality. St. Tikhon of course embraced this principle, and his deviation from it merely entailed practical accommodations necessitated by difficulties facing the early Orthodox immigration to America. It is both dishonest and an insult to the Saint's memory that his use of justifiable oikonomia in what was then a relatively new mission is now invoked as a standard of Orthodox practice in a local Church that is more than two centuries old.

The following articles may be of interest to some:

The Question of Long Hair in Orthodox Christianity
Why Greek Orthodox Priests Have Beards

An icon of Jesus Christ Pantocrator from Macedonia, from the 14th Century showing him with unshorn hair and beard.
Most pictures, statues and icons have Our Lord as having long hair!


How do monergists respond to Bible verses that support the doctrine of synergism?

A monergist response to your verses would, I think, be along the lines of:
"Be perfect". We can have fellowship through Jesus taking our sins. In Christ we have His perfection. Who will be in Christ? Those that the Father has given Him. John 17:2 - " He should give eternal life to as many as you have given Him." "have given Him" It's a done deal.
"commandments". When God gives a command He either does or does not give the grace for that command to be obeyed. If His will is that someone obeys that command He gives them the grace to obey. If His will is that they do not obey He does not give the grace for that command to be obeyed. Only in this way can He be preeminent in all things. see Colossians 1: 18 "that in all things He may have the preeminence".
Rev 3:20. We choose to open or to leave shut. But, why do we choose one thing or another? We choose on the basis of who we are. Who are we? That depends upon how we were made.
We choose on the basis of how we were made. Judgement is having to live with the consequences of how we were made. Goats and sheep don't make themselves. Goats and sheep are separated on the basis of what they are, i.e. how God made them.
"Freedom". Gal 5:13. Freedom here  is freedom from the Law, Old Testament Law, not freedom from some philosophic system of "free will".
[Our wills are not free of how and why God made them].
At one level monergism and synergism are about how people are saved but these spill over into wider issues about ultimate responsibility for evil. Synergism I suggest tries to protect God from the accusation that He is ultimately responsible for evil by saying something He created is autonomous from Him and this created evil. But synergism attacks God's uniqueness because by saying something other than God created evil it means that something other than God can create.
Monergists believe that at the start of every causal chain is one starting point, the Alpha of Rev 21:6. When God, who is light, created darkness [Isaiah 45:7] He had a holy motive for doing so. There is a single purpose behind everything in creation-"all things were created through Him and for Him", Col 1:16.


What internal evidence supports the historicity of Abraham?

Internal evidence from the New Testament
This is a Christian site, so a Christian defense for the historicity of Abraham can be based on what Jesus or the apostles say about Abraham.  If Jesus / the apostles implied Abraham exists, then there's your internal evidence from the New Testament.
Some examples:

Jesus's genealogy in Matt 1:17.  Christians believe that Jesus is 100% human and in His human nature He is a natural descendant of Abraham

Jesus's claim that he existed before Abraham (John 8:58)

Jesus said that many Gentiles will have a feast with Abraham in the Kingdom of God (Matt 8:11)

James used Abraham as example of faith in the sense that we can emulate a REAL person from the past (James 2:21-24)

External corroboration from Ancient Near Eastern research
While we have not found a non-Biblical text / inscription naming Abraham, there has been a lot of progress in Ancient Near Eastern research in the past 100 years fueled by new discoveries in the 20th century which both Biblical and secular scholars used to correlate elements of the Genesis story with non-Israelite texts, customs, and material remains.
To answer the claim of Thomas L. Thompson you quoted I offer this excellent essay by Martin J. Selman: "Comparative Customs and the Patriarchal Age" published by IVP in a 1980 book "Essays on the Patriarchal Narratives", listing the current (yet) uncontested correlations between ANE research and Biblical text after reviewing 3 waves of scholarship: 1) Consensus, 2) Destruction of Consensus, 3) Current Discussion.  The claim by Thomas L. Thompson was covered in section 2 (Destruction of Consensus), but the essay responded in section 3 with a review of later research that tempered his rather negative assessment.
Another value of this essay is in providing believers with a level-headed and a responsible scholarly (non-polemical) guidelines for comparison (section 3.4 to 3.6).  This quote is from section 4 (Conclusion), emphasis mine:

When the biblical and nonbiblical material is subject to proper control, the way is still open for the social customs of the patriarchal narratives to be legitimately illustrated and supported from a variety of historical contexts in the ancient Near East. The following list includes those examples which remain valid in the light of the conditions for comparison discussed above.
... (skipped: list of 12 currently uncontested correlations)
Since the large majority of these examples show that the patriarchal customs can be compared without difficulty with a wide range of material from the ancient Near East, it may be concluded that the patriarchal narratives accurately reflect a social and historical setting which belongs to the second and first millennia BC. More precise dates must of course be derived from other considerations, but neither van Seters' preference for first millennium material nor Thompson's assessment of the essentially nonhistorical character of the narratives can be supported by the evidence of the social customs. From the independent viewpoint of the historian, therefore, the social parallels make the historical existence of the patriarchs more likely.
But our conclusion also has hermeneutical and theological implications. Two examples must suffice. That Laban should conclude the details of Jacob's marriages twenty years after the marriages were agreed (Gn. 31:50), even though a marriage contract would normally have been drawn up at the beginning, is further evidence of his duplicity and of the difficulties with which Jacob had to contend. By contrast, Abraham's refusal to take a second wife or a concubine of his own in the face of Sarah's continuing infertility gives a new insight into his regard for Sarah's position as well as his faith in God's provision of the promised heir. A proper appreciation of the social and historical dimension of the patriarchal narratives thus leads to a more accurate understanding of Genesis' theological contribution, as in the specific application of Abraham's faith.


What is the name of the view that the Earth is 4 billion years old, but God inserted human beings 5000 years ago?

The Gap Theory

The Gap Theory proposes that there was a long gap in time between Genesis 1:1 and 1:2, and that the rest of Genesis 1 is effectively a re-creation story, after the creation and chaos of the gap. Most Gap Theory proponents interpret Genesis 1:2-1:31 as describing a six day creation, and would date it around six thousand years ago, as the following genealogies are thought to indicate.

Exegetically the theory is very poor, and is as incompatible with conventional science as young earth creationism, so its popularity is now greatly reduced.

Homo divinus

Some Christians believe in a historical Adam, who was the first 'real' human - the first made in the image of God, the first with a spirit (or soul), the first moral human etc. God specially created Adam and Eve, perhaps as a new creation, or perhaps by transforming one of the prior human-like creatures, and this took place around six thousand years ago. John Stott coined the name Homo divinus for the spiritual human made in the image of God:

  But my acceptance of Adam and Eve as historical is not incompatible with my belief that several forms of pre-Adamic ‘hominid’ may have existed for thousands of years previously. These hominids began to advance culturally. They made their cave drawings and buried their dead. It is conceivable that God created Adam out of one of them. You may call them homo erectus. I think you may even call some of them homo sapiens, for these are arbitrary scientific names. But Adam was the first homo divinus, if I may coin a phrase, the first man to whom may be given the Biblical designation ‘made in the image of God’. Precisely what the divine likeness was, which was stamped upon him, we do not know, for Scripture nowhere tells us. But Scripture seems to suggest that it includes rational, moral, social, and spiritual faculties which make man unlike all other creatures and like God the creator, and on account of which he was given ‘dominion’ over the lower creation. (John Stott, Understanding the Bible: Expanded Edition; 54-56)

This kind of theory is better than the Gap Theory, and is not incompatible with conventional science (though in fact it would be completely scientifically non-falsifiable.) Theologically though it has major problems: if all conventional science is to be accepted, but Adam and Eve lived only so long ago, then does that mean that peoples such as Aboriginal Australians who migrated to Australia some forty thousand years ago and then were out of communication with most of the world are not Homo divinus, that they are not actually made in the image of God?

I don't have any references on this, but I'd imagine that some extend the Homo divinus theory to say that, rather than God making a single couple, Adam and Eve, God transformed all Homo sapiens into Homo divinus at the same time. This solves the problem I just raised, but then loses the main benefit of Stott's Homo divinus theory: having a historical Adam and a historical fall.

Progressive creationism

One view that has some similarities to the previous one is Progressive creationism, which says that through the ages God has directly and specially created each life form, including humans. This view accepts the conventional age of the earth and fossils dates, but rejects evolution. Instead each kind of creature was created as is by God, and has remained the same since that time. As with Homo divinus, progressive creationists would accept that there were homonids before modern Homo sapiens. Seeing as there appears to be evidence of Homo sapiens long before six thousand years ago, many progressive creationists would probably say that God created them before that time, but some might say that God created them when the Biblical genealogies would indicate.


Can people pray with those from other denominations?

Toward the secondary question of how Catholics approach ecumenical prayer, ecumenism is generally encouraged by the Catechism and the teaching of the bishops.

What is allowed to the faithful Catholic is to join in those spiritual activities which we can engage in together in an honest way, since the Catholic church teaches that all Christians have a real unity by way of our baptism, but also recognizes that we have real differences which have resulted in a visible separation. These activities are most commonly prayer, bible study, and praise/singing (not "worship" as Catholics define it). A Catholic may also be a reader in a non-Catholic gathering if invited. Catholics may also attend services/celebrations which are recognized as valid by the Catholic church, such as the baptism of a relative.

What is not allowed is to participate with other Christians in ways that would be dishonest. For example, in the Catholic conception of communion, when a Catholic receives the Eucharist, they are expressing that they are one with Christ as well as that they are one with the Catholic community. In most cases, the Catholic is also professing a significantly different understanding of what is happening during communion. For these reasons, a Catholic could not participate with a non-Catholic in a communion service, because what they would be "saying" by their actions would be dishonest. Catholics are also taught that it is not appropriate to participate in non-Catholic services if their intent is to seek the things they should be seeking from the Mass. So it would be illicit for a Catholic to attend a non-Catholic service instead of attending Mass in most cases.

This also highlights the differences in the structure of different Christian communities. What it means to be Catholic is to be in communion with the preaching and teaching authority of the bishop of one's diocese, which is handed down from the apostles, where the bishop is himself in communion with the bishop of Rome. However, in other churches, such as many Protestant or Orthodox national churches, there may not necessarily be universal agreement on what is expected, or there may be significantly different local interpretations of canon law or other more universal "touchpoint" documents.

This is not the main question, but I can provide references on particular points if helpful. However, it is usually best to create a separate question if you want to receive several in-depth answers with references.


How did all the animals fit into Noah's ark?

I suppose there is one other possible answer:

  It was a miracle.

That would put it in the "how did Jesus walk on water?" and "how did Jesus feed thousands of people with a few fish sandwiches?" category.


A few points:

The "bunch of kids who made fun of Elijah's bald spot" were not a bunch of kids, (the KJV's translation is quite unfortunate here,) but a bunch of youths (meaning teens or young men.) It was Elisha, not Elijah, that they were making fun of, and laughing at him for being bald wasn't their offense.  This incident took place soon after Elijah's ascension into heaven, and they were telling him to "go up, thou bald head."  In other words, "hey baldie, if your master could go up to heaven, why can't you do it too?"  Insinuating that God's chosen servant didn't have the power of God with him as his predecessor did was their sin, and it was a pretty serious sin indeed, because it can lead others around them away from the Lord.

Also, it says that there were over 40 youths involved in the incident.  That's not "a bunch of kids," it's a small mob, and "mocking" in Old Testament times was not always confined to simple verbal taunting.  They could very well have been putting the prophet in physical danger.  One man, old enough to be going bald, against 40 strong young men isn't good odds, so why shouldn't he call upon the Lord for some help with his predicament?

As for the more general cases of "smiting the wicked," your "most superficial ethical level" is superficial indeed, as it only looks at the situation from a mortal perspective.  To understand these actions, we need to look at it from an eternal perspective.

The scriptures make it clear that we will be judged according to our works, and that salvation comes by the Atonement of Jesus Christ, whose power we can apply to ourselves through faith and repentance.  We have free will, to choose good or evil, for as long as that's a meaningful choice.  But when a person or a civilization reaches the point where they've sunk so low that there are no good choices to make, and no faith or desire to repent in their hearts, then there's no point in keeping them around any longer, especially if doing so would harm others.  (For example, by allowing them to live long enough to bring children into the world that would never end up having a chance to live righteously due to the environment they were raised in.)  At that point, God destroys them to prevent greater harm to the world.

It's an act of love, done by an all-knowing God who understands the consequences, which makes it fundamentally different from a murder committed by a sociopath who doesn't know (or most likely even care) what his victims might have done had they continued to live.


Will Agnostics and Atheists go to Hell? (Catholic)

The Catholic Church teaches that particular judgment is final

You had originally asked a hybrid question: what Catholics believe, and what the biblical basis is for not believing in Jesus and going to Hell.  While a variety of scripture refers to those being with Christ, and those not being with Him, and  the afterlife in parables (the Goats and the Sheep, Rich man Lazarus and the poor man, the thief on the cross) we'll address the Catholic  teaching question.

The Bible: belief in Jesus Christ is required to get to Heaven

In the answer LRL provides, you see two succinct Biblical references in John 3:16 and John 14:6 to a perquisite of going to Heaven being belief in Jesus Christ.  Under Christian soteriology, that is commonly referred to as salvation through Jesus Christ.  (Numerous other scriptural passages refer to that as well).

The Catholic Church teaches that only through Jesus Christ may one get to Heaven.

The modern doctrinal statement is in Dominus Iesus as described in the linked answer by @AthanasiusOfAlex.  There is more to it than simply saying "I believe in Jesus" as shown in Matthew 7:21-23:

  21 “Not everyone who says to Me, ‘Lord, Lord,’ shall enter the kingdom of heaven, but he who does the will of My Father in heaven.  22 Many will say to Me in that day, ‘Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?’  23 And then I will declare to them, ‘I never knew you; depart from Me, you who practice lawlessness!’

The above passage underscores the point that a Christian has to walk the walk, not just talk the talk, in order to come to the Kingdom of Heaven.  An agnostic (doesn't believe nor disbelieve) or an atheist (refuses to believe) will not "talk the talk" although either may now and again walk the walk without doing so as part of a Christian witness.   (Old school Catholic teaching; Council of Trent: there is no salvation outside the church.  We have a Q&A on that somewhere).

Particular judgment and how that relates to Heaven and Hell.

Insofar as Hell being the final disposition for a given soul (rather than simply not going to Heaven) here is the top level teaching of the Catholic Church from the Catechism (note that there are scriptural references):

I. THE PARTICULAR JUDGMENT

  CCC 1021 Death puts an end to human life as the time open to either
  accepting or rejecting the divine grace manifested in Christ.
  592  The New Testament speaks of judgment primarily in its
  aspect of the final encounter with Christ in his second coming, but
  also repeatedly affirms that each will be rewarded immediately after
  death in accordance with his works and faith. The parable of the
  poor man Lazarus and the words of Christ on the cross to the good
  thief, as well as other New Testament texts speak of a final destiny
  of the soul--a destiny which can be different for some and for
  others.593

References here are : 592 2d Timothy 1:9-10 ; 593 Luke 16:22; 23:43; Matthew 16:26; 2d Corinthi and 5:8; Philippians 1:23; Hebrews 9:27; 12:23

  CCC 1022 Each man receives his eternal retribution in his immortal soul at the very moment of his death, in a particular judgment that refers his life to Christ: either entrance into the blessedness of heaven-through a purification 594 or immediately, 595 -- or immediate and everlasting damnation. 596

References are: 594 Council of Lyons II (1274): DS 857-858; Council of Florence (1439):DS 1304- 1306; Council of Trent (1563):DS 1820; 595 Benedict XII, Benedictus Deus (1336):DS 1000-1001; John XXII, Ne super his (1334):DS 990; 596 596 Cf. Benedict XII, Benedictus Deus (1336):DS 1002.

There is a discrete teaching about Hell in the Catechism

  IV. HELL

  CCC 1033 We cannot be united with God unless we freely choose to love him.  But we cannot love God if we sin gravely against him, against our neighbor or against ourselves: "He who does not love remains in death.  Anyone who hates his brother is a murderer, and you know that no murderer has eternal life abiding in him." 612 Our Lord warns us that we shall be separated from him if we fail to meet the serious needs of the poor and the little ones who are his brethren. 613 To die in mortal sin without repenting and accepting God's merciful love means remaining separated from him for ever by our own free choice. This state of definitive self-exclusion from communion with God and the blessed is called "hell."

References are 612 1 John 3:14-15; 613 Matthew 25:31-46.

In the case of the atheist, the decision to self exclude from communion with God is willful.  For an agnostic, the case is not as clear since the problem the agnostic faces is as much doubt (not enough basis to believe?) as any willful separation from God by not deciding to believe.  On that basis, there may be some hope of salvation for an agnostic but it's an extreme edge case.  Given all of the scriptural guidance to seek Christ, and the parables that point out that failing to follow Him and to follow His teachings has dire consequences (what you did not do for the least of my children), the agnostic ends up in the same situation as the atheist: one needs to both walk the walk and talk the talk to be with Christ.  For that matter, the Christians who "say it but don't do it" are in a the same boat when particular judgment arrives.  (See the cited verse in Matthew 7:21-23).

Bottom Line; that elevator goes to the basement

There is solid scriptural basis and Catholic teaching that non-believers (atheists and agnostics) have only one destination in the afterlife and it isn't Heaven.  Beyond attempts at evangelization, what Catholics can do is pray for the atheists and agnostics, and to ask our Lord to have mercy on them as we pray that He has mercy on us.  It's the least we can do, and for some it's the most we can do.

{DS = Denzinger-Schonmetzer, Enchiridion Symbolorum, definitionum et declarationum de rebus fidei et morum (1965)(Handbook of Creeds and Definitions)}


What does it mean that the Believers Eastern Church (in Asia) is an "Ancient-Future Church"?

On the surface, ancient-future churches claim to speak across generations and draw equally upon ancient (hymns, chant, candles, communion) and techno-modern (alt. rock, art, ambient, projection, video) sources. An American example of this would be the hi-tech megachurches that host anything from rock concerts to communions.

Underneath that modern, millenial-attracting exterior lies a method developed re-design & re-purpose churches, emphasizing proselytization & assimilation:

(from Ancient-Future Evangelism: Making Your Church a Faith-Forming Community)

It endeavours to reach its goal by introducing "levels", akin to New-Age religions such as Scientology.

In sociology, this concept is called gamification and is widespread in social networks and mobile apps. Gamification is hugely popular amongst millenials and Generation Z.

Ancient-Future is a reaction to attempt countering the decline in worldwide religiosity, which is especially hurting first-world Christianity. According to the latest Pew studies on the matter, the regional percentage of the population identifying as Christian will decline significantly in Western regions by 2050:

The situation for Asia is a stagnant, but this is largely due to Christianity being concentrated in just a few Asian countries with a higher birth rate than the West.

The motivations for this modernized recruitment approach are twofold:

many millenials grow up much less influenced and knowledgeable of doctrine as the previous generations. They also grew up and are accustomed to virtually immediate access to scientific facts and are as a result, better versed in critical thinking
the most loyal age group in first-world churches will be largely deceased by 2050


According to Catholicism, did Jesus really use wine at the Last Supper?

Did Jesus really use wine at the Last Supper? Has the Catholic Church made any research into the prospects of Jesus having used fresh grape juice?
Tradition holds that according to the Catholic Church, Christ used real wine at the Last Supper and not fresh grape juice.
This has been the constant tradition for centuries within both Catholic and Orthodox Churches. No Church Father suggests that Christ ever used grape juice in lieu of wine at the Last Supper.
Let us remember that Jesus’ first public miracle was to turn water into wine at the Wedding Feast at Cana. His last miracle was to change the bread and wine into his flesh and blood!
For example, St. Cyril of Jerusalem(c. 313 – 386 AD) speaks to us as Jesus using wine for the Eucharist.

"The bread and the wine of the Eucharist before the holy invocation of the adorable Trinity were simple bread and wine, but the invocation having been made, the bread becomes the body of Christ and the wine the blood of Christ" (Catechetical Lectures 19:7 [A.D. 350]).
"Do not, therefore, regard the bread and wine as simply that; for they are, according to the Master’s declaration, the body and blood of Christ. Even though the senses suggest to you the other, let faith make you firm. Do not judge in this matter by taste, but be fully assured by the faith, not doubting that you have been deemed worthy of the body and blood of Christ…[Since you are] fully convinced that the apparent bread is not bread, even though it is sensible to the taste, but the body of Christ, and that the apparent wine is not wine, even though the taste would have it so,…partake of that bread as something spiritual, and put a cheerful face on your soul" (ibid., 22:6, 9). - The Church Fathers on the Holy Eucharist

To this day, during the Passover Feast the Jewish faithful drink wine. In fact, they serve four cups of wine.

The four cups of wine, known in Hebrew as arba kosot, are drunk by each participant at the Passover seder service.
This ceremony is prescribed by the Mishnah as a duty to be observed by even the poorest man (Pes. 10: 1). The four cups are drunk in the following order: (1) the Kiddush at the start of the seder; (2) at the conclusion of the main part of the Haggadah which ends with the Ge'ullah ("Redemption") benediction; (3) at the end of the Grace after Meals; and (4) at the conclusion of the Nishmat hymn ("Birkat ha-Shir"). Only the second and fourth cups were added for the seder meal since the drinking of the two other cups forms part of every meal on Sabbaths and holidays. The reason for four cups is based by the rabbis upon the midrashic interpretation of Exodus 6:6–7, where four different terms of deliverance are employed: "I will bring you out … deliver you … redeem you … and will take you to Me for a people," etc. (Ex. R. 6:4). Other symbolic explanations for the four cups are that they correspond to the four cups of Pharaoh mentioned in Genesis, ch. 40, or to the four ancient kingdoms which oppressed Israel and for which God requites Israel with four cups of consolation (TJ, Pes. 10:1, 37b–c).
Other examples of the special symbolic significance of the number four in the Haggadah are the Four Questions ("Mah Nishtannah"). Four Sons, and the four types of food at the seder meal: unleavened bread (matzah), lamb, bitter herbs, and ḥaroset. Some rabbis in the Talmud required a fifth cup of wine for the fifth expression of redemption "I shall bring you" (Pes. 118a, according to the text found in R. Hananel and Alfasi); this became symbolized in the cup of Elijah on the seder table. The four cups of wine should be drunk in a reclined position, as in Roman times reclining was a sign of freedom. Each cup has to contain at least a ¼ log (0.137 liter; Sh. Ar, OḤ 472:9). Red wine is to be preferred but because of the blood accusations in Europe, white wine was often used (see Blood Libel ). - Passover: Four Cups of Wine

Freshly pressed grapes do not remain as such in warmer climates. Freshly pressed grapes will ferment quite naturally on it’s own.
It is simply impossible to keep the juice from crushed grapes from fermenting without modern refrigeration and pasteurization techniques. So yes, the wine was alcoholic.
Besides that the Passover is held in March or April! That is not the time for grape harvesting in the northern hemisphere. You have to wait about six months more for that in Israel. Thus another indication that it was indeed wine used at the Last Supper.

All fruit when crushed or rotten will have naturally occurring alcohol. As long as there is sugar, yeast and water alcohol will happen. Most commercially purchased fruit juice has a small amount of alcohol in it when you purchase it.

Low-alcoholic beverage Sparkling cider, sodas, and juices naturally contain trace amounts or no alcohol. Some fresh orange juices are above the UK 'alcohol free' limit of 0.05% ABV, as are some yogurts and rye bread.

Ethanol distillation is used to separate alcoholic beverages into what are advertised as non-alcoholic beverages and spirits; distilled wine produces low alcohol wine and brandy (from brandywine, derived from Dutch brandewijn, "burning wine"),1 distilled beer may be used to produce low-alcohol beer and whisky.

However alcoholic beverages cannot be further purified to 0.00% alcohol by volume by distillation. In fact, most beverages labeled non-alcoholic contain 0.5% ABV as it is more profitable than distilling it to 0.05% ABV often found in products sold by companies specializing in non-alcoholic beverages. - Can alcohol (ethanol) exist in nature without the intervention of man?

Some get into the subject matter of yeast in the Passover Feast because the Ancient Jews ate unleavened bread. That is to say without yeast in the making of Matzo. However, Moses makes to such prohibition in the use of grape juice for wine, whether by natural means or manually added by man to aid fermentation. The Ancient Jews ate Matzo because they ate in haste.


Introduction

From the excerpts below, the Letter of St. James was addressed to the Christians of the Diaspora, who lived outside Palestine among the Gentiles; the First Letter of St. Peter was addressed to Christian communities living in various parts of Asia Minor. the environment there was hostile, which meant that Christians' perseverance was at risk; the Second Letter of St. Peter is addressed to Christians in general; the First letter of St. John, the fact that addresses are not mentioned suggests that it was a kind of circular letter sent to a number of Christian communities; the Second letter of St. John is addressed to a local church, very probably one in Asia Minor. the Third Letter of St. John is addressed to a Christian called Gaius, and perhaps through him to a group of Christian faithful; and finally the letter of St. Jude does not specify whom it is addressed to, but it was probably written originally for Christians converts from Judaism.

While each letter has its own content and purpose and there is very little common to them all, St. Augustine says that they were written to refute errors which were beginning to raise their head.

Below follows the excerpts in detail.

  The Catholic Letters

  After the thirteen letters of St.Paul and the letter to the Hebrews
  come seven other letters (one by St. James, two by St. Peter, three by
  St. John and one by St. Jude) which since the time of Origen, Eusebius
  and St. Jerome have been known as the 'catholic' letters, letters to
  the Church at large, not directed to a particular church or
  individual: the second and third letters of St. John, even though they
  are addressed to a private individual are regarded as appendixes to
  his first letter and are also included in the 'catholic letters'
  category.

  Source: A GUIDE TO THE BIBLE | ANTONIO FUENTES

And also

  The Catholic Letters

  The canon of the books of the New Testament includes, along with the
  Pauline corpus (the thirteen letters of St. Paul and the letter of
  Hebrews), a group of seven others which Tradition usually calls the
  "Catholic Letters" - that written by St. James, two by St. Peter,
  three by St. John and one by St. Jude. Apparently the reason for
  grouping them together is not because they are similar in doctrine or
  style, but simply to distinguish them from the body of Pauline
  letters. This grouping already existed from around the end of the
  fourth century AD (cf. Eusebius of caesarea, Eccl. Hist., 3, 25,
  2-3). The books have not always been given this position in the New
  testament: the great Vatican and Siniatic codexes place them after the
  book of the Acts of the Apostles; from the time of St. Jerome onwards,
  all bibles place the immediately after the writings of St. Paul, just
  before the book of Revelation. Nor were they all in the same sequence
  as now: we often find St.Peter's two letters coming first; however,
  from St. Jetome onwards most manuscripts place them where they
  normally appear in printed bibles.

  The name "catholic" was applied by Origen to the First Letter of
  Peter, the first of John and that of Jude. Later Eusebius and St.
  Jerome extended the title to cover all seven letters. It seems that
  they were given this name because they were addressed to the whole
  Church and not to particular communities or persons, as St. Paul's
  letters were. By extension, the title was applied as to 1 and 2 John,
  even those letters were sent to specific individuals.

  Each letter has its own content and purpose and there is very little
  common to them all. St. Augustine says that they were written to
  refute errors which were beginning to raise their head (cf. De fide
  et operibus, 14, 21). Certainly, they all evidence the teaching and
  catechesis which was being given to the first communities of
  Christians. For most part, using pastoral tone, they deal with
  doctrinal instruction and moral teaching, all aimed at encouraging
  people to live deeply Christian lives.

  Source: THE NAVARRE BIBLE NEW TESTAMENT COMPACT EDITION

From the same Bible:

  The Letter of St. James

  Excerpt

  The letter is addressed to "the twelve tribes in the dispersion"
  (1:1), that is, the Christians of the Diaspora, who lived outside
  Palestine among the Gentiles. Anything we know about the circumstances
  in which it was written comes from the letter itself: that is, certain
  defects were beginning to appear which threatened the spiritual health
  of those communities. There is debate about the date of composition,
  but it was probably written in the 60s AD, although some scholars
  propose a later date.

  The First Letter of St. Peter

  Excerpt

  [...] the date of composition is usually put around the year 64 or 67,
  the possible years of Peter's martyrdom [...] It is addressed to
  Christian communities living in various parts of Asia Minor. the
  environment there was hostile, which meant that Christians'
  perseverance was at risk. many of them were converts from paganism,
  probably recent ones. Hence the constant reminders about Baptism [...]
  As we can see from the final greeting, the letter was written in
  "Babylon" (5:13), that is, Rome, the capital of the empire, as it used
  to be called symbolically [...]

  The main of the apostle seems to be to console Christians and exhort
  them to stay true to the faith in the midst of difficulties and
  persecution.

  The Second Letter of St. Peter

  Excerpt

  [...] internal analysis makes it more difficult to attribute the
  letter to Peter [...] the Tradition of the Church has associated the
  Second Letter of Peter with the person of the apostle.

  The letter is addressed to Christians in general, even though some
  expressions imply that it was originally addressed to Christian
  communities in Greece or Asia Minor. the dates of composition that
  have been suggested run from year 60 to the end of the first century.

  The letters of St. John

  Excerpt

  The First Letter of John [...] the fact that addresses are not
  mentioned suggests that it was a kind of circular letter sent to a
  number of Christian communities. It is likely that it was written,
  after the fourth Gospel, to the Christian communities of Asia Minor
  mentioned in the book of Revelation (Rev 2:1-3:22). [...]

  The Second and Third Letters of St. John [...] In both letters the writer introduces himself as the "elder" (2 Jn 1; 3 Jn 1). The Second letter is addressed to the "elect lady and her children" (v. 1), a figurative way of referring to a local church, very probably on in Asia Minor. The Third Letter is addressed to a Christian called Gaius (v. 1), and perhaps through him to a group of Christian faithful. [...]

  The second Letter was written as a word of warning at a time when the danger from heretics was not as great as that revealed in 1 John. the counsel the writer gives is along the same lines as that contained in the First Letter. the Third Letter, although it does not contain new teachings, is valuable testimony to the fidelity of the early Christian communities and a model of type of letters of commendation mentioned elsewhere in the New Testament [...]

  The letter of St. Jude

  Excerpt

  [...] The letter does not specify whom it is addressed to, but it was probably written originally for Christians converts from Judaism. We do not know when it was written; maybe around the year 70.

  The author seeks to exhort the faithful to put up a fight for the faith delivered to them (v. 3), reminding them that the apostles warned them in advance that ungodly people would appear on the scene, people given to licentiousness (vv. 17-18). maybe the author wrote the letter because he had learned that people like this had already wormed their way into those Christian communities (v. 4).


Did the myth of the holy grail originate from Catholicism?

Although the Grail folklore seems to stem from the same centuries as the crusades due to Arthurian legends. Here is a little insight to its' origins. The origins are a mix of cultures. The medieval Church took no official stance on Grail folklore.

  The Roots of the Holy Grail

  Academic consensus gives the Grail a Celtic origin. The foremost campaigner for this view is Arthurian scholar Roger Sherman Loomis, whose book, The Grail: From Celtic Symbol to Christian Myth (1963), traces it to Irish tales of cauldrons and drinking horns that never run empty as well as accounts of journeys to the Happy Otherworld. The maiden Grail-bearer is based on the personified Sovereignty of Ireland, a woman who gives her cup only to the worthy. These elements were transmitted to Wales, then to Brittany, with Breton storytellers spreading them around northern France where the medieval romances first appeared. Loomis assumes that the material had been much altered by misunderstandings and oral process: There was no one "original" Grail myth.

  But it was the connection with the Holy Eucharist that fixed the Grail in medieval minds. The old myths might never have gained such popularity without the Christianization that brought them in line with medieval iconography and devotional practice.

  Grail romances appeared just as Eucharistic devotion was gaining favor, expressed in the elevation of the Host during Mass, Corpus Christi processions, preachers' parables, and miracle stories. Hosts that levitate, bleed, discriminate among recipients, serve as the sole food of saints, and reveal visions of Christ appear often in Eucharistic miracles and in Grail adventures. Devout contemplation of the elevated or exposed Host was believed to convey not only grace but well-being and protection, as does an encounter with the Grail.

  The medieval Church took no official position on Grail romances. But the cathedral of Valencia claims to possess the actual vessel, a red stone cup from the time of Christ mounted as a splendid chalice during the Middle Ages. Its legend — which owes nothing whatever to the romances — claims that it was sent to Spain by the Roman martyr St. Lawrence. Donated to the cathedral in 1437, it's kept in a special chapel and was once used for Mass by Pope John Paul II. - The Real History of the Holy Grail

Valencia Chalice

  Pope John Paul II himself celebrated Mass with the Holy Chalice in Valencia in November 1982. In 2006 at Valencia, Pope Benedict XVI also celebrated with the Holy Chalice, on this occasion saying “this most famous chalice”, words in the Roman Canon said to have been used for the first popes until 4th century in Rome, and supporting in this way the tradition of the Holy Chalice of Valencia. - The Holy Chalice of Valencia: Is it the Holy Grail?


All my days are ordained before I was born?

Foreordination is not the same as predestination.

Ordination in the Bible typically refers to being set apart to the office in the Priesthood, for example, the members of the house of Aaron were ordained to take care of the tabernacle during the exodus and later the temple.

A great example of someone who did not follow through with his ordination is Kind David. Even though he was ordained to great things he committed great sin and lost his opportunity.

When the bible refers to foreordination it means that God has identified the potential of certain individuals and ordained them to do great things before they were born. That said, someone does not have to follow through with their potential because we were each given what's probably the most difficult gift for any father to give: the freedom to choose.


Where does God draw the line when it comes to Sin?

Well, taking advntage of the God's mercy and forgivness is certainy not a right thing. In my opinion, unless we compeletly sway out of God's way, we should not worry to much about what kind of sins we do everyday; unless it is serious. We are humans, after all, we all make mistakes. Like Jesus said in the bible:

  Matthew 26:41:
  41 Stay awake and pray for strength against temptation. The spirit wants to do what is right, but the body is weak."

In the end, it is not how we can avoid sinning, but it is how we can be more like Christ. We will always have transgressions, but we should be trying to make it better.


What is the biblical basis for in the catholic theology of a priest being in "persona christi"?

A priest is not being in "persona Christi" but the priest ACTS in the person of Christ(persona Christi) in pronouncing the words that comprise part of a sacramental rite.

For example, in the Mass, the Words of Institution, by which the bread becomes the Body of Christ and the wine becomes the Precious Blood. The priest and bishop ACT in the person of Christ the head in their leadership of the Church.

2 Corinthians 2:10

  Whomever you forgive anything, so do I. For indeed what I have
  forgiven, if I have forgiven anything, has been for you in the
  presence of Christ,

Naturally, therefore, without consulting the Greek text, this verse would not necessarily leap out at one as being about the priesthood. But the Greek text says that St Paul forgave sins “en prosopo Christou”.

“Prosopon” in Greek literally means “face”. In the Trinitarian debates of the 4th Century, the Greeks used it to translate Tertullian’s use of the latin term “persona” for what we now commonly refer to as “the Persons” of the Holy Trinity. Working the other way, when Jerome translated made his new Latin translation of the bible, he used “persona” to translate “prosopon” in 2 Corinthians 2:10, thus making the text read:

  10 cui autem aliquid donatis et ego nam et ego quod donavi si quid
  donavi propter vos in persona Christi 11 ut non circumveniamur a
  Satana non enim ignoramus cogitationes eius

In English translations, both the Douay-Rheims and the King James Bible follow suit in translating “en prosopo Christou” as “in the person of Christ.”

As you can see, this certainly lends strong support to the Catholic doctrine of the priesthood (cf. CCC p1548 quoting 24 Pius XII, Mediator Dei: “Now the minister, by reason of the sacerdotal consecration which he has received, is truly made like to the high priest and possesses the authority to act in the power and place of the person of Christ himself (virtute ac persona ipsius Christi).)

Source


Is the God Calvinists believe in unjust?

I think the issue here is that you are trying to examine one point of doctrine outside of the context of the whole system of doctrines that it fits into. If you take the Calvinistic doctrine of predestination by itself and tack it on to a generic pseudo-protestant view of salvation, you'll end up with a problem such as the one you describe. God becomes unjust because your definition of justice is supported by a theological framework that Calvinistic theology would say is a broken framework. Even as a Calvinist I can see how people who try to examine a specific doctrine such as predestination can conclude it to be nonsensical or even offensive. However that is not the end of the story.

In order to judge such a doctrine, you must consider it in the context of all the same presuppositions and other related doctrines. This will be a very simplistic outline of some issues that need to be brought into the discussion rather than a full treaties on the issues, but I hope it helps provide a starting point.

First of all, predestination cannot be considered without also resolving the issue of original sin. According to a Calvinistic interpretation of scripture, the idea of original sin when traced through all of scripture paints a picture of man as totally depraved: in other words he will not (and cannot) on his own volition and power act or choose anything that is truly good in God's eyes. It's a hard pill to swallow because man's prideful nature always wants to defend himself to the last; yet I have come to believe this is both the true nature of all men and exactly the picture Scripture paints of him.

This leaves us with an unsettling conclusion quite different from the one you pose in your question. If the doctrine of total depravity is to be believed, no man on earth would ever, given an opportunity, voluntarily choose to follow God or believe in Christ as savior. The only just thing for God to do with such rebellious prideful people is to destroy them.

This creates a whole new problem. Suddenly God is not unjust for not saving some, he is unjust for saving any at all! The problem with justice, for a Calvinist, comes at the point of "unconditional election", whereby God opts to save some in spite of the fact that they have fulfilled no condition for deserving salvation such as believing or doing works or whatever. Now the Doctrines of Grace are starting to all play off of each other!

The problem of injustice -- that God would knowingly justify (make right) and acquit somebody who themselves had done nothing but wrong and of whom justice would demand punishment -- is resolved in the propitiatory act of Christ where somebody who had done no wrong and justly deserved life was "made sin" and put in our law place and punished on our behalf. Whose law place did he step into? Again according to the same set of interpretations one must understand Limited Atonement, or the idea that Christ choose to be the atonement for a specific set of people, his chosen. In a very real sense this choice is arbitrary because those people did not do anything specific to deserve it -- hence we cannot boast in any choice or act of our own but only in Christ who rescued us -- but it is not unjust for him not to choose other than he did. The alternative is that he died in an attempt to save more, but was ineffective in so much as it only "worked" for some people who had enough good sense to recognize the value of his work of their own accord (an idea ruled out earlier by Total Depravity).

The system can be rounded out with the other doctrines such as Irresistible Grace where God does not fail to lead those he has acquitted to repentance faith and repentance and holy lives being transformed to be like Christ; and Perseverance of the Saints whereby those he has saved and truly worked in cannot be pulled out of his hand by any force of Satan or shortcoming of their own.

Obviously these points need to be examined in the light of the Scriptures. They basically stand or fall together. If the Bible as God's inerrant word really is pointing in the direction of any of these points, it must also be consistent to tell us about the others. Great care must be taken in two areas:

Not to use some system that fails to take into account all the points in Scripture to interpret for us whether some doctrine is true or not. Predestination makes little sense to some theological systems, but it must not be thrown out because it doesn't fit a definition of justice that isn't the one defined by Scripture. This is the error I think you have made.
Not to read into Scripture some point not actually found in the text because it has to fit our system. Quite frankly this is the error Calvinists are more likely to fall into. If the interpretive framework fails to shed light on the whole of Scripture or is contradicted by it on any point, one must start over and examine it's presuppositions.

I am convinced that the only set of presuppositions and interpretive methods that leads to a framework that can consistently interpret the whole of Scripture is the one that leads to all of these Doctrine of Grace -- yet it is not a perfect system and we must remain humble in the knowledge that our limited understandings of God's works are always going to be flawed in so far as we have not yet been made perfect in glory!

Lastly I think it's worth noting that it is impossible to approach Scripture without some interpretive framework. There is no such thing as entirely unbiased reading. Even if the text in question was written in your own time and language, words are meaningless with out certain presuppositions. For example if you fail to presuppose that I wrote this post in English and rather assume it to be Bengali, it will be no more than gibberish. In testing it can be shown that reading the text using English grammar and vocabulary lead to a much more useful understanding. Likewise if we do not approach Scripture with certain assumptions about how it was inspired or is meant to be interpreted as a whole, we will not come away with as deep or true an understanding of it. While these are pre-suppositions (pre because they must be made first and tested later) they can be shown to make more sense when taken together as a whole.


Did Adam and Eve have children in paradise?

The crux of this question is really How long was it before Adam and Eve sinned?

The biblical record only has the following facts:

Adam and Eve's first child was Cain, and the second Abel, by virtue of Genesis 4.
Genesis 4 also suggests that Seth was not born until after Cain killed Abel, an act that could not have occurred in the Garden.
Genesis 5 says that Adam was 130 when Seth was born, so that establishes an upper limit for the length of the time on the garden.  (I will repeat my assertion that had I been Eve, I only would have lasted about 32 minutes before getting kicked out, nonetheless I digress.)

This means that the only two children who could have been born in the Garden are Cain and Abel.

Circumstantially, I would have to suggest that the evidence would make a much stronger case for the children being born after rather than before:

There is no mention of anyone other than Adam or Eve being cast out.  (And the Lillith thing is just Jewish legend.)
The fact that the narrative records the conception of Cain after Genesis 3 gives no reason to suspect it happened before.