Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men because all sinned—(For until the law sin was in the world, but sin is not imputed when there is no law. Nevertheless, death reigned from Adam to Moses, even over those who had not sinned according to the likeness of the transgression of Adam, who is a type of Him who was to come. But the free gift is not like the offense. For if by the one man’s offense many died, much more the grace of God and the gift by the grace of the one Man, Jesus Christ, abounded to many. And the gift is not like that which came through the one who sinned. For the judgment which came from one offense resulted in condemnation, but the free gift which came from many offenses resulted in justification. For if by the one man’s offense death reigned through the one, much more those who receive abundance of grace and of the gift of righteousness will reign in life through the One, Jesus Christ.) Therefore, as through one man’s offense judgment came to all men, resulting in condemnation, even so through one Man’s righteous act the free gift came to all men, resulting in justification of life. For as by one man’s disobedience many were made sinners, so also by one Man’s obedience many will be made righteous. (Rom 5:12-19)
What has Adam’s guilt got to do with us? Why are we held responsible for his sin when we were not even born when he committed it? Did not God say: “The parents will not die for the children, nor the children for the parents, but the soul which has sinned, it shall die.” How then shall we defend this doctrine? The soul, I say, which has sinned, it shall die. We have become sinners because of Adam’s disobedience in the following manner.… After he fell into sin and surrendered to corruption, impure lusts invaded the nature of his flesh, and at the same time the evil law of our members was born. For our nature contracted the disease of sin because of the disobedience of one man, that is, Adam, and thus many became sinners. This was not because they sinned along with Adam, because they did not then exist, but because they had the same nature as Adam, which fell under the law of sin. Thus, just as human nature acquired the weakness of corruption in Adam because of disobedience, and evil desires invaded it, so the same nature was later set free by Christ, who was obedient to God the Father and did not commit sin.
Cyril of Alexandria, Explanation of the Letter to the Romans