Nicene and Post-Nicene Fathers: Series I/Volume V/On the Merits and Forgiveness of Sins, and on the Baptism of Infants/Book II/Chapter 45

Chapter 45 [XXVIII.]—The Law of Sin is Called Sin; How Concupiscence Still Remains After Its Evil Has Been Removed in the Baptized.

This law of sin, however, which the apostle also designates “sin,” when he says, “Let not sin therefore reign in your mortal body, that ye should obey it in the lusts thereof,” does not so remain in the members of those who are born again of water and the Spirit, as if no remission thereof has been made, because there is a full and perfect remission of our sins, all the enmity being slain, which separated us from God; but it remains in our old carnal nature, as if overcome and destroyed, if it does not, by consenting to unlawful objects, somehow revive, and recover its own reign and dominion. There is, however, so clear a distinction to be seen between this old carnal nature, in which the law of sin, or sin, is already repealed, and that life of the Spirit, in the newness of which they who are baptized are through God&#8217;s grace born again, that the apostle deemed it too little to say of such that they were not in sin; unless he also said that they were not in the flesh itself, even before they departed out of this mortal life. “They that are in the flesh,” says he, “cannot please God; but ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you.” And indeed, as they turn to good account the flesh itself, however corruptible it be, who apply its members to good works, and no longer are in that flesh, since they do not mould their understanding nor their life according to its principles; and as they in like manner make even a good use of death, which is the penalty of the first sin, who encounter it with fortitude and patience for their brethren&#8217;s sake, and for the faith, and in defence of whatever is true and holy and just,—so also do all “true yokefellows” in the faith turn to good account that very law of sin which still remains, though remitted, in their old carnal nature, who, because they have the new life in Christ, do not permit lust to have dominion over them. And yet these very persons, because they still carry about Adam&#8217;s old nature, mortally generate children to be immortally regenerated, with that propagation of sin, in which such as are born again are not held bound, and from which such as are born are released by being born again. As long, then, as the law by concupiscence dwells in the members, although it remains, the guilt of it is released; but it is released only to him who has received the sacrament of regeneration, and has already begun to be renewed. But whatsoever is born of the old nature, which still abides with its concupiscence, requires to be born again in order to be healed. Seeing that believing parents, who have been both carnally born and spiritually born again, have themselves begotten children in a carnal manner, how could their children by any possibility, previous to their first birth, have been born again?