Have you an infant child? Do not let sin get any opportunity, but let him be sanctified from his childhood; from his very tenderest age let him be consecrated by the Spirit. Fearest thou the Seal on account of the weakness of nature? O what a small-souled mother, and of how little faith! Why, Anna even before Samuel was born 1 Sam. 1:10 promised him to God, and after his birth consecrated him at once, and brought him up in the priestly habit, not fearing anything in human nature, but trusting in God. You have no need of amulets or incantations, with which the Devil also comes in, stealing worship from God for himself in the minds of vainer men. Give your child the Trinity, that great and noble Guard.
Be it so, some will say, in the case of those who ask for Baptism; what have you to say about those who are still children, and conscious neither of the loss nor of the grace? Are we to baptize them too? Certainly, if any danger presses. For it is better that they should be unconsciously sanctified than that they should depart unsealedand uninitiated.
A proof of this is found in the Circumcision on the eighth day, which was a sort of typical seal, and was conferred on children before they had the use of reason. And so is the anointing of the doorposts, Ex. 12:22 which preserved the firstborn, though applied to things which had no consciousness. But in respect of others I give my advice to wait till the end of the third year, or a little more or less, when they may be able to listen and to answer something about the Sacrament; that, even though they do not perfectly understand it, yet at any rate they may know the outlines; and then to sanctify them in soul and body with the great sacrament of our consecration. For this is how the matter stands; at that time they begin to be responsible for their lives, when reason is matured, and they learn the mystery of life (for of sins of ignorance owing to their tender years they have no account to give), and it is far more profitable on all accounts to be fortified by the Font, because of the sudden assaults of danger that befall us, stronger than our helpers.
But, one says, Christ was thirty years old when He was baptized, Lk. 3:23 and that although He was God; and do you bid us hurry our Baptism?— You have solved the difficulty when you say He was God. For He was absolute cleansing; He had no need of cleansing; but it was for you that He was purified, just as it was for you that, though He had not flesh, yet He is clothed with flesh. Nor was there any danger to Him from putting off Baptism, for He had the ordering of His own Passion as of His own Birth. But in your case the danger is to no small interests, if you were to depart after a birth to corruption alone, and without being clothed with incorruption. And there is this further point for me to consider, that that particular time of baptism was a necessity for Him, but your case is not the same. He manifested Himself in the thirtieth year after His birth and not before; first, in order that He might not appear ostentatious, which is a condition belonging to vulgar minds; and next, because that age tests virtue thoroughly, and is the right time to teach. And since it was needful for Him to undergo the passion which saves the world, it was needful also that all things which belong to the passion should fit into the passion; the Manifestation, the Baptism, the Witness from Heaven, the Proclamation, the concourse of the multitude, the Miracles; and that they should be as it were one body, not torn asunder, nor broken apart by intervals. (Oration 40.17, 28-29)