We are fortunate to have commentary from the second century by St Hippolytus [a.d. 170–236.] who was the disciple of Irenæus. We often raise the question, "Why did Jesus have to be baptized if He was sinless?" He explains why John, who resisted baptizing Jesus because he felt unworthy and inferior to Him thinking that he should be baptized by Jesus, baptized Him who was God Himself.
Hyppolytus shows how Christ comforted John,
And what saith the Lord to him? “Suffer it to be so now, for thus it becometh us to fulfil all righteousness.” (Matt 3:15) “Suffer it to be so now,” John; thou art not wiser than I. Thou seest as man; I foreknow as God. It becomes me to do this first, and thus to teach. I engage in nothing unbecoming, for I am invested with honour. Dost thou marvel, O John, that I am not come in my dignity? The purple robe of kings suits not one in private station, but military splendour suits a king: am I come to a prince, and not to a friend? “Suffer it to be so now for thus it becometh us to fulfil all righteousness:” I am the Fulfiller of the law; I seek to leave nothing wanting to its whole fulfilment, that so after me Paul may exclaim, “Christ is the fulfilling of the law for righteousness to every one that believeth.” (Rom 10:4) “Suffer it to be so now, for thus it becometh us to fulfil all righteousness.” Saint Hyppolytus tells us why Jesus was baptized, speaking from viewpoint of Jesus,
Baptize me, John, in order that no one may despise baptism. I am baptized by thee, the servant, that no one among kings or dignitaries may scorn to be baptized by the hand of a poor priest. Suffer me to go down into the Jordan, in order that they may hear my Father’s testimony, and recognise the power of the Son. “Suffer it to be so now, for thus it becometh us to fulfil all righteousness.” Then at length John suffers Him. “And Jesus, when He was baptized, went up straightway out of the water: and the heavens were opened unto Him; and, lo, the Spirit of God descended like a dove, and rested upon Him. And a voice (came) from heaven, saying, This is my beloved Son, in whom I am well pleased.” (Matt 3:16-17) Jesus wanted to emphasize the role of the priest in baptizing those who chose to follow Him. He wanted all to hear the testimony of the Father so others would accept Him as His Son as this was the time He began His public ministry.
Saint Hyppolytus continues uplifting our sight even higher,
Do you see, beloved, how many and how great blessings we would have lost, if the Lord had yielded to the exhortation of John, and declined baptism? For the heavens were shut before this; the region above was inaccessible. We would in that case descend to the lower parts, but we would not ascend to the upper. But was it only that the Lord was baptized? He also renewed the old man, and committed to him again the sceptre of adoption. For straightway “the heavens were opened to Him.” A reconciliation took place of the visible with the invisible; the celestial orders were filled with joy; the diseases of earth were healed; secret things were made known; those at enmity were restored to amity. For you have heard the word of the evangelist, saying, “The heavens were opened to Him,” on account of three wonders. For when Christ the Bridegroom was baptized, it was meet that the bridal-chamber of heaven should open its brilliant gates. And in like manner also, when the Holy Spirit descended in the form of a dove, and the Father’s voice spread everywhere, it was meet that “the gates of heaven should be lifted up.” (Ps 24: 7) “And, lo, the heavens were opened to Him; and a voice was heard, saying, This is my beloved Son, in whom I am well pleased.”
Most significantly we see in this event that the heavens are opened for all mankind who follow Him and join with Him through Baptism to become His adopted children. Christ shows us that we begin our Journey with Him through baptism. This is a Holy Sacrament where heavens are opened and we join with The Holy Trinity to be transformed, born again, so we can become like Him and have eternal life in His kingdom as one of His children.
Christ’s baptism in the Jordan was A “theophany,” in that the world was granted a revelation of the Holy Trinity. The Father testified from on high to the divine Sonship of Jesus; the Son received His Father’s testimony; and the Spirit was seen in the form of a dove, descending from the Father and resting upon the Son.
In the hymn of the Feast we sing, “Christ has appeared and enlightened the world.” Thus, January 6 is also known as the Feast of Lights. The Church celebrates on this day the illumination of the world by the light of Christ.
Reference: Ante-Nicene Fathers, vol 5, Hyppolytus, Discourse on Holy Theophany