Romans 5:12

Rom 5:12 Therefore, just as sin came into the world through one man, and death came through sin, and so death spread to all because all have sinned (NRSV)

The grammar behind the greek for “because” (eph w) here is a bit obscure. In the ancient Latin Vulgate translation it reads:
“…and so death spread to all men, through one man, in whom all men sinned." (Vulgate, translated into English)
Augustine, for example, famously based much of his concept of Original Sin on the Vulgate's dubious translation here.

However the reading of the ancient Greek theologians seems rather to have been:
“... thus death passed to all men, on account of which all have sinned” (Orthodox New Testament)

These readings put the causation quite differently:
One man => one sin => one death, and all likewise sinning => own deaths. (NRSV)
One man => in whom were all men => one sin, in which all men participated => all die (Latins)
One man => one sin => one death => death passed onto all => own deaths => own sins (Greeks)

The Greek theology perhaps needs clarifying further regarding how death passed to all, and how own deaths => own sins. A commonly used phrase by the greek theologians was “what is born of a moral is mortal”, ie Adam's transgression made him mortal and we who are born of Adam are mortal too. Similarly it was thought that a world in which death is present causes sin, as people fear death and act selfishly, and so death reigns in a tyranny of oppression over people and enslaves them into sin.

Anyway, the point of this post is to say that I am increasingly being convinced that the third interpretation is the correct one. There are several reasons for this:
1) The apparent universal acceptance of this interpretation by the ancient greeks suggests it is the most obvious reading based on greek grammar.
2) It makes the sentence in Romans 5:12 more consistent in terms of style, ie each phrase of the sentence is a logical consequence of the previous phrase, rather than the last part of the sentence being backward.
3) Otherwise there seems to be a paradox in the verse – do all die because of Adam's sin, or because of their own?
4) It's more consistent with Paul's theology of death “reigning” and as the ultimate enemy to say that death causes sin rather than vice versa.
5) It's more consistent with Romans 5:19.
6) It's more consistent with the use of the obscure phrase (eph w) in other places in the NT (eg 2 Cor 5:4, Phil 3:12, Phil 4:10).