John 1:32-34
“And John bare record, saying, I saw the Spirit descending from the heaven like a dove, and It abode upon Him. And I knew Him not: but He that sent me to baptize with water, the Same said unto me, Upon whom you shall see the Spirit descending, and remaining on Him, the same is He which baptizes with the Holy Ghost. And I saw, and bare record that this is the Son of God.”
He puts the “I knew Him not” repeatedly. On what account, and wherefore? He was His kinsman according to the flesh. “Behold,” says the angel, “your cousin Elisabeth, she also has received a son.” That therefore he might not seem to favor Him because of the relationship, he repeats the “I knew Him not.” And this happened with good reason; for he had passed all his time in the wilderness away from his father's house.
How then, if he knew Him not before the descent of the Spirit, and if he then for the first time recognized Him, did he forbid Him before baptism, saying, “I have need to be baptized by You, and You come to me?”, since this was a proof that he knew Him very well. Yet he knew Him not before or for a long time, and with good cause; for the marvels which took place when He was a child, as the circumstances of the Magi and others the like, had happened long before, while John himself was very young, and since much time had elapsed in the interval, He was naturally unknown to all. For had He been known, John would not have said, “That He should be made manifest to Israel, therefore am I come baptizing.”
3. Hence it remains clear to us, that the miracles which they say belong to Christ's childhood, are false, and the inventions of certain who bring them into notice. For if He had begun from His early age to work wonders, neither could John have been ignorant of Him, nor would the multitude have needed a teacher to make Him known. But now he says, that for this he has come, “that He might be made manifest to Israel”; and for this reason he said again, “I have need to be baptized by You.” Afterwards, as having gained more exact knowledge of Him, he proclaimed Him to the multitude, saying, “This is He of whom I said, After me comes a Man which is preferred before me.” For “He who sent me to baptize with water,” and sent me for this end, “that He should be made manifest to Israel,” Himself revealed Him even before the descent of the Spirit. Wherefore even before He came, John said, “One comes after me who is preferred before me.” He knew Him not before he came to Jordan and baptized all men, but when He was about to be baptized, then he knew Him; and this from the Father revealing Him to the Prophet, and the Spirit showing Him when He was being baptized to the Jews, for whose sake indeed the descent of the Spirit took place. For that the witness of John might not be despised who said, that “He was before me,” and that “He baptizes with the Spirit,” and that “He judges the world,” the Father utters a Voice proclaiming the Son, and the Spirit descends, directing that Voice to the Head of Jesus. For since one was baptizing, the other receiving baptism, the Spirit comes to correct the idea which some of those present might form, that the words were spoken of John. So that when he says, “I knew Him not,” he speaks of former time, not that near to His baptism. Otherwise how could he have forbidden Him, saying, “I have need to be baptized by You”? How could he have said such words concerning Him?
“But,” says one, “how then did not the Jews believe? For it was not John only that saw the Spirit in the likeness of a dove.” It was, because, even if they did see, such things require not only the eyes of the body, but more than these, the vision of the understanding, to prevent men from supposing the whole to be a vain illusion. For if when they saw Him working wonders, touching with His own hands the sick and the dead, and so bringing them back to life and health, they were so drunk with malice as to declare the contrary of what they saw; how could they shake off their unbelief by the descent of the Spirit only? And some say, that they did not all see it, but only John and those of them who were better disposed. Because even though it were possible with fleshly eyes to see the Spirit descending as in the likeness of a dove, still not for this was it absolutely necessary that the circumstance should be visible to all. For Zacharias saw many things in a sensible form, as did Daniel and Ezekiel, and had none to share in what they saw; Moses also saw many things such as none other has seen; nor did all the disciples enjoy the view of the Transfiguration on the mount, nor did they all alike behold Him at the time of the Resurrection. And this Luke plainly shows, when he says, that He showed Himself “to witnesses chosen before of God.”
“And I saw, and bare record that this is the Son of God.”
Where did he “bear record that this is the Son of God?” he called Him indeed “Lamb,” and said that He should “baptize with the Spirit,” but nowhere did he say of Him, “Son of God.” But the other Evangelists do not write that He said anything after the baptism, but having been silent as to the time intervening, they mention the miracles of Christ which were done after John's captivity, whence we may reasonably conjecture that these and many others are omitted. And this our Evangelist himself has declared, at the end of his narrative. For they were so far from inventing anything great concerning Him, that the things which seem to bring reproach, these they have all with one voice and with all exactness set down, and you will not find one of them omitting one of such circumstances; but of the miracles, part some have left for the others to relate, part all have passed over in silence.
I say not this without cause, but to answer the shamelessness of the heathen. For this is a sufficient proof of their truth-loving disposition, and that they say nothing for favor. And thus as well as in other ways you may arm yourselves for trial of argument with them. But take heed. Strange were it that the physician, or the shoemaker, or the weaver, in short all artists, should be able each to contend correctly for his own art, but that one calling himself Christian should not be able to give a reason for his own faith; yet those things if overlooked bring only loss to men's property, these if neglected destroy our very souls. Yet such is our wretched disposition, that we give all our care to the former, and the things which are necessary, and which are the groundwork of our salvation, as though of little worth, we despise.
4. That it is which prevents the heathen from quickly deriding his own error. For when they, though established in a lie, use every means to conceal the shamefulness of their opinions, while we, the servants of the truth, cannot even open our mouths, how can they help condemning the great weakness of our doctrine? How can they help suspecting our religion to be fraud and folly? How shall they not blaspheme Christ as a deceiver, and a cheat, who used the folly of the many to further his fraud? And we are to blame for this blasphemy, because we will not be wakeful in arguments for godliness, but deem these things superfluous, and care only for the things of earth. He who admires a dancer or a charioteer, or one who contends with beasts, uses every exertion and contrivance not to come off worst in any disputes concerning him, and they string together long panegyrics, as they compose their defense against those who find fault with them, and cast sneers without number at their opponents: but when arguments for Christianity are proposed, they all hang their heads, and scratch themselves, and gape, and retire at length the objects of contempt.
Source: Homilies on the Gospel of John (New Advent)