The Eastern Fathers reflect at length upon Christ’s baptism as a potent symbol of the Incarnation in all its paradoxical majesty and mystery. An Orthodox hymn for Epiphany notes that in Jesus’s baptism we see “The River of Joy… baptized in the stream” (The Festal Menaion, 295). The One through whom all water was made and in which all things subsist is himself submerged in muddy Jordan. How can this be?...
Christ’s baptism is a particular act of humility. St. Matthew’s Gospel dwells on the inversion of Jesus being baptized by John. “I have need to be baptized of thee,” John protests, “and comest thou to me?” (Matt. 3:14). St. Mark’s compact account draws attention not so much to the incongruity between John and Jesus but rather to the startling nature of John’s baptism. John preached “the baptism of repentance for the remission of sins,” and it is this baptism to which Jesus submits, despite having no sins to remit. Thus, in his first act in Mark’s Gospel, Christ explicitly identifies himself with sinners. Later Jesus will describe his impending Passion as “the cup that I drink” and “the baptism with which I am baptized” (Mark 10:38-39, ESV). From the outset, he expresses a freely chosen solidarity with sinners, and this identification of the Sinless Christ with sinful humanity comes to its awful and glorious climax on the cross.Christ's baptism also inaugurates sacramental baptism, and so it reveals not only who Christ is -- but also who we are:
...we should never forget that, in being baptized into Christ’s death, we are also, as St. Paul tells us, “risen with him through the faith of the operation of God, who hath raised him from the dead” (Col. 2:12). We share in his death and in his resurrection, and we indeed partake of his divine life (2 Pet. 1:4).
At every baptism, the heavens are rent, the Spirit descends, and the voice of God speaks:
“Thou art my beloved child, in whom I am well pleased.”You can read (or hear) the whole thing.