Question: Why was Christ baptized?
He was not baptized because He had sins that needed to be cleansed. St. John the Baptist himself recognized this. In the Gospel of Matthew, it says: "Then cometh Jesus from Galilee to Jordan unto John, to be baptized of him. But John forbad him, saying, I have need to be baptized of thee, and comest thou to me?" (Matthew 3:12-14). Christ's answer gives us the first answer to your question: "And Jesus answering said unto him, Suffer [allow] it to be so now: for thus it becometh us to fulfil all righteousness. Then he suffered him" (Matthew 3:15).
So what does it mean that "it becometh us to fulfil all righteousness"?
St. John Chrysostom says this:"He shows also how this “becometh” Him. How then doth it so? “In that we fulfill the whole law;” and to express this He said, “all righteousness.” For righteousness is the fulfilling of the commandments. “Since then we have performed all the rest of the commandments,” saith He, “and this alone remains, it also must be added: because I am come to do away the curse that is appointed for the transgression of the law. I must therefore first fulfill it all, and having delivered you from its condemnation, in this way bring it to an end. It becometh me therefore to fulfill the whole law, by the same rule that it becometh me to do away the curse that is written against you in the law: this being the very purpose of my assuming flesh, and coming hither” (Homily 12:1 on Matthew).
Christ fulfilled all the law. He was circumcised on the eighth day; He was subject to his earthly parents; etc. He lived the perfect life that we have failed to live. If it was only necessary for Christ to have been incarnate and then to die, God could have allowed Herod to have killed him as an infant. But it was also necessary that he live the life that we should have lived, and then to die and rise again.
St. Chromatius says: "Jesus therefore descended to fulfill all the observances of the law, and in this context he was baptized by John in Galilee at the Jordan" (Tractate on Matthew 12:1, quoted in Ancient Christian Commentary on Scripture: New Testament, Vol. 1A, Manlio Simonetti, ed. (Downers Grove, IL: Intervasity Press, 2001) p. 51).
St. Gregory Palamas says: ""Thus it becommeth us to fulfil all righteousness (Matt. 3:15), that is, that I may leave no divine commandment undone, thus perfectly justifying human nature and filling it more visibly with divine and eternal grace. For when I receive baptism at your hands, I shall manifestly draw down it from above the Spirit of adoption. (Homily 59 "On Holy Baptism and Repentance," Christopher Veniamin, trans. Saint Gregory Palamas: The Homilies (Waymart, PA: Mount Thabor Publishing, 2009), p. 492).
St. Cyril of Alexandria says: " It was necessary therefore that the Word of the Father, when He humbled Himself unto emptiness, and deigned to assume our likeness, should become for our sakes the pattern and way of every good work. For it follows, that He Who in every thing is first, must in this also set the example. In order therefore that we may learn both the power itself of holy baptism, and how much we gain by approaching so great a grace, He commences the work Himself; and, having been baptized, prays that you, my beloved, may learn that never-ceasing prayer is a thing most fitting for those who have once been counted worthy of holy baptism" (Homily 11 on the Gospel of Luke).
St. Jerome gives three reasons why Christ was baptized: "First, because he was born a man, that he might fulfill all justice and humility of the law. Second, that by his baptism he might confirm John's baptism. And third, that by sanctifying the waters of the Jordan through the descent of the dove, he might show the Holy Spirit's advent in the baptism of believers" (Commentary on Matthew 1:2:13, quoted in Ancient Christian Commentary on Scripture: New Testament, Vol. 1A, Manlio Simonetti, ed. (Downers Grove, IL: Intervasity Press, 2001) p. 51).
Christ also imaged His death and resurrection in His baptism. St. Gregory Palamas says: "For at the time of His descent into Hades, He went under the earth for our sake, and on returning thence, He opened all things both to Himself and to us, not just things on or around the earth, but highest heaven itself, to which afterwards He ascended bodily, "wither the forerunner is for us entered" (Heb. 6:20). Just as he foreshadowed the mystical bread and cup, and then handed on this mystery to the faithful to perform for their salvation (I Cor 11:25; Luke 22:17-20), so He mystically foretold His descent into Hades and His ascent from their through this baptism of His, and afterward passed on this sacrament to believers to perform that they may be saved. He allowed Himself what was painful and difficult, but bestowed on us communion in His sufferings right from the start through these painless means, causing us, according to the apostle, to be "planted together in the likeness of his death" (Rom. 6:5), that in due time we might also be vouchsafed the promised resurrection" (Homily 60 "On the Holy Feast of Theophany," Christopher Veniamin, trans. Saint Gregory Palamas: The Homilies (Waymart, PA: Mount Thabor Publishing, 2009), p. 495f).
