⭐ The key text for the Western doctrine of original sin was mistranslated by one word in the Latin version Augustine read. ⚠ On the timeline it is placed at 412, the year Augustine built his argument on it (On the Spirit and the Letter); the Old Latin version took shape long before this, and this entry itself has no exact date.
The issue
“so death passed to all men because all sinned” — what does this because mean in the original Greek?
Claim
The common understanding of the Greek eph hō (ἐφ᾽ ᾧ) is because: death came to all because all, each one, sinned.
Counterclaim
The Old Latin version Augustine read rendered it in quo — in whom, that is: all sinned in Adam. This rendering directly supports the seminal identity view of original sin: the whole human race sinned in Adam really, and not merely representatively.
Aftermath
⚠ This is not meant to wipe out Augustine's doctrine of original sin at a stroke — his position rests on far more than this one verse, and the Eastern church also has a doctrine of original sin (only a different one). But this verse carries great weight in the chain of argument for the Western doctrine of original sin, and part of that weight comes from the translation. ⭐ The point of this entry is one of method: a doctrine sometimes takes shape not only through Scripture and logic, but also through what the translation in one's hands looks like. Homoousios on thread 1 and physis on thread 2 are examples of the same kind — a good share of the disagreements in the history of doctrine are first of all problems of language.