I believe a key cause of the Original Sin issue is the interpretation of the verse Romans 5:12:
Dia touto hosper di' henos anthropou he hamartia eis ton kosmon eiselthen kai dia dia tes hamartias ho thanatos, kai houtos eis pantas anthropous ho thanatos dielthen, eph' ho pantes hemarton
δια τουτο ωσπερ δι ενος ανθρωπου η αμαρτια εις τον κοσμον εισηλθεν και δια της αμαρτιας ο θανατος και ουτως εις παντας ανθρωπους ο θανατος διηλθεν εφ ω παντες ημαρτον
This is a verse that I have never ever seen translated accurately, except by the Orthodox New Testament
, by Holy Apostles Convent. Here are some different versions of this verse:
Propterea sicut per unum hominem in hunc mundum peccatum intravit et per peccatum mors et ita in omnes homines mors pertransiit in quo omnes peccaverunt
Modern English translations usually get it something like this:
Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men, because all sinned
The patristic rendering of the verse is:
Therefore, just as through one man sin came into the world, and through sin [or, the sin] death, and thus death passed through to all men, on account of which all sinned. (My translation; Holy Apostles Convent also says "on account of which.")
The phrase "eph' ho/in quo" was mistakenly taken to mean "in whom" (i.e. in Adam) in the Latin tradition, hence we all sinned "in Adam."
However, the very ambiguous preposition "epi" literally means "on," and by extension, it often means "because of." The relative pronoun's antecedent is death, not Adam. Technically, it is ambiguous, but it would have to refer all the way back to the beginning of the sentence to be indicating Adam.
Let's look at some historical interpretations of this verse.Thomas Aquinas, from Summa:
The Apostle says (Rom. 5:12): "Death passed upon all men in whom all have sinned."
I answer that, According to the Catholic Faith we must firmly believe that, Christ alone excepted, all men descended from Adam contract original sin from him; else all would not need redemption [*Cf. Translator's note inserted before TP, Q] which is through Christ; and this is erroneous. The reason for this may be gathered from what has been stated (A), viz. that original sin, in virtue of the sin of our first parent, is transmitted to his posterity, just as, from the soul's will, actual sin is transmitted to the members of the body, through their being moved by the will. Now it is evident that actual sin can be transmitted to all such members as have an inborn aptitude to be moved by the will. Therefore original sin is transmitted to all those who are moved by Adam by the movement of generation.
Reply to Objection 1: It is held with greater probability and more commonly that all those that are alive at the coming of our Lord, will die, and rise again shortly, as we shall state more fully in the TP (XP, Q, A, OBJ). If, however, it be true, as others hold, that they will never die, (an opinion which Jerome mentions among others in a letter to Minerius, on the Resurrection of the Body---Ep. cxix), then we must say in reply to the objection, that although they are not to die, the debt of death is none the less in them, and that the punishment of death will be remitted by God, since He can also forgive the punishment due for actual sins.
Reply to Objection 1: Original sin is taken away by Baptism as to the guilt, in so far as the soul recovers grace as regards the mind. Nevertheless original sin remains in its effect as regards the "fomes," which is the disorder of the lower parts of the soul and of the body itself, in respect of which, and not of the mind, man exercises his power of generation. Consequently those who are baptized transmit original sin: since they do not beget as being renewed in Baptism, but as still retaining something of the oldness of the first sin.
Reply to Objection 3: Just as Adam's sin is transmitted to all who are born of Adam corporally, so is the grace of Christ transmitted to all that are begotten of Him spiritually, by faith and Baptism: and this, not only unto the removal of sin of their first parent, but also unto the removal of actual sins, and the obtaining of glory.
--Summa, part I, question 81, article 3.
This interpretation is a little different from that of St. Augustine, whose commentary on Romans I unfortunately cannot find online. However, here is a link where you can find his interpretation of it: http://books.google.com/books?id=zJh2iwKAdYYC&printsec=frontcover&dq=augustine%27s+commentary+on+romans&source=bl&ots=7At796sio2&sig=eef8EJ4aDzcQMZJklq_cFkoNnkg&hl=de&ei=8ETnTKrMOIW8lQfmsaHxCw&sa=X&oi=book_result&ct=result&resnum=7&ved=0CFQQ6AEwBg#v=onepage&q&f=false
Just for fun, John Calvin
Sin entered into the world, etc. Observe the order which he keeps here; for he says, that sin preceded, and that from sin death followed. There are indeed some who contend, that we are so lost through Adam’s sin, as though we perished through no fault of our own, but only, because he had sinned for us. But Paul distinctly affirms, that sin extends to all who suffer its punishment: and this he afterwards more fully declares, when subsequently he assigns a reason why all the posterity of Adam are subject to the dominion of death; and it is even this — because we have all, he says, sinned. But to sin in this case, is to become corrupt and vicious; for the natural depravity which we bring, from our mother’s womb, though it brings not forth immediately its own fruits, is yet sin before God, and deserves his vengeance: and this is that sin which they call original.
Apparently, St. Augustine and Calvin follow the "because all sinned" interpretation, although they still disagree as to the doctrine itself. (IMO, Calvin's interpretation that all men deserve condemnation for actual sins, thus justifying condemnation for Original Sin, is a cop-out for having to explain injustice in God.)
Now, St. John Chrysostom
How then did death come in and prevail? “Through the sin of one.” But what means, “for that all have sinned?” This: he having once fallen, even they that had not eaten of the tree did from him, all of them, become mortal.
St. John emphasizes the inheritance of mortality
. Why mortality leads to sin he does not explain. (It's typical of him to bypass the theological issue and hurry towards the verses most pertinent to a layman.)
This view fits in uncannily well with the Eastern emphasis on humanity's dual enslavement to sin and death, the inseperability of sin and death, and the fact that Christ saved us by abolishing the two. See Hebrews 2:14-15:Forasmuch then as the children are partakers of flesh and blood, he also himself likewise took part of the same; that through death he might destroy him that had the power of death, that is, the devil; And deliver them who through fear of death were all their lifetime subject to bondage.
I apologize for a really dry post, but hopefully it will help clarify the discussion, and add some more substance to it.