Nicene and Post-Nicene Fathers: Series I/Volume V/On the Merits and Forgiveness of Sins, and on the Baptism of Infants/Book I/Chapter 10

Chapter 10.—The Analogy of Grace.

No doubt all they imitate Adam who by disobedience transgress the commandment of God; but he is one thing as an example to those who sin because they choose; and another thing as the progenitor of all who are born with sin. All His saints, also, imitate Christ in the pursuit of righteousness; whence the same apostle, whom we have already quoted, says: “Be ye imitators of me, as I am also of Christ.” But besides this imitation, His grace works within us our illumination and justification, by that operation concerning which the same preacher of His [name] says: “Neither is he that planteth anything, nor he that watereth, but God that giveth the increase.” For by this grace He engrafts into His body even baptized infants, who certainly have not yet become able to imitate any one. As therefore He, in whom all are made alive, besides offering Himself as an example of righteousness to those who imitate Him, gives also to those who believe on Him the hidden grace of His Spirit, which He secretly infuses even into infants; so likewise he, in whom all die, besides being an example for imitation to those who wilfully transgress the commandment of the Lord, depraved also in his own person all who come of his stock by the hidden corruption of his own carnal concupiscence. It is entirely on this account, and for no other reason, that the apostle says: “By one man sin entered into the world, and death by sin, and so passed upon all men; in which all have sinned.” Now if  I were to say this, they would raise an objection, and loudly insist that I was incorrect both in expression and sense; for they would perceive no sense in these words when spoken by an ordinary man, except that sense which they refuse to see in the apostle. Since, however, these are the words of him to whose authority and doctrine they submit, they charge us with slowness of understanding, while they endeavour to wrest to some unintelligible sense words which were written in a clear and obvious purport. “By one man,” says he, “sin entered into the world, and death by sin.” This indicates propagation, not imitation; for if imitation were meant, he would have said, “By the devil.” But as no one doubts, he refers to that first man who is called Adam: “And so,” says he, “it passed upon all men.”