Therefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
All Commentaries on Romans 5:12 Go To Romans 5
John Chrysostom
AD 407
Paul inquires as to how death came into the world and why it prevailed. It came in and prevailed through the sin of one man and continued because all have sinned. Thus once Adam fell, even those who had not eaten of the tree became mortal because of him.