3 But we, who know the economy, adore His mercy, because He has come to save and not to judge the world. Wherefore John, the forerunner of the Lord, who before knew not this mystery, on learning that He is Lord in truth, cried out, and spoke to those who came to be baptized of him, “O generation of vipers,” why do you look so earnestly at me? “I am not the Christ;” I am the servant, and not the lord; I am the subject, and not the king; I am the sheep, and not the shepherd; I am a man, and not God.
By my birth I loosed the barrenness of my mother; I did not make virginity barren. I was brought up from beneath; I did not come down from above. I bound the tongue of my father; I did not unfold divine grace. I was known by my mother, and I was not announced by a star. I am worthless, and the least; but “after me there comes One who is before me” — after me, indeed, in time, but before me by reason of the inaccessible and unutterable light of divinity. “There comes One mightier than I, whose shoes I am not worthy to bear: He shall baptize you with the Holy Ghost, and with fire.” I am subject to authority, but He has authority in Himself.
I am bound by sins, but He is the Remover of sins. apply the law, but He brings grace to light. teach as a slave, but He judges as the Master. I have the earth as my couch, but He possesses heaven. I baptize with the baptism of repentance, but He confers the gift of adoption: “He shall baptize you with the Holy Ghost, and with fire.” Why do you give attention to me? I am not the Christ.
Source: Discourse on the Holy Theophany (New Advent)