First of all, he did it as an example for us.
Jesus’ entire life is an example for us of how to be human and how to follow God. His will was that people would repent of their sin and be baptized by John as a sign of their commitment to follow God. As a result, Jesus decided to be baptized, to show us how important it is to convert our hearts and make a public act of faith.
Pope Benedict XVI, in his book Jesus of Nazareth, gives us another reason. He says that Jesus’ baptism anticipates what He did for all mankind on the cross:
- The act of descending into the waters of this Baptism implies a confession of guilt and a plea for forgiveness in order to make a new beginning. In a world marked by sin, then, this Yes to the entire will of God also expresses solidarity with men, who have incurred guilt but yearn for righteousness. The significance of this event could not fully emerge until it was seen in light of the Cross and Resurrection. Descending into the water, the candidates for Baptism confess their sin and seek to be rid of their burden of guilt. What did Jesus do in the same situation? Luke, who throughout his Gospel is keenly attentive to Jesus' prayer, and portrays him again and again at prayer -- in conversation with the Father -- tells us that Jesus was praying while he received Baptism (cf. Lk 3:21). Looking at the events in light of the Cross and Resurrection, the Christian people realized what happened: Jesus loaded the burden of all mankind's guilt upon his shoulders; he bore it down into the depths of the Jordan. He inaugurated his public activity by stepping into the place of sinners. His inaugural gesture is an anticipation of the Cross. He is, as it were, the true Jonah who said to the crew of the ship, "Take me and throw me into the sea" (Jon 1:12). The whole significance of Jesus' Baptism, the fact that he bears, "all righteousness," first comes to light on the Cross: The Baptism is an acceptance of death for the sins of humanity, and the voice that calls out "This is my beloved Son" over the baptismal waters is an anticipatory reference to the Resurrection. This also explains why, in his own discourses, Jesus uses the word baptism to refer to his death (cf. Mk 10:38; Lk 12:50). (p. 17-18)
By descending into the waters of the Jordan, Jesus takes the place of all sinners, who were being called by John to do what Jesus was doing. He does the same thing on the Cross, where He pays the price for all man’s sin.
His going under the water is symbolic of burial and the destruction of sin that will take place on the cross. We see this purpose for water in the flood of Noah’s day, which buried and destroyed all the sin in the world.
His rising out of the water is symbolic of His resurrection. The dove that rests above Him and the voice that cries out from the heavens point to the glory that will be His once His work is finished.
St. Thomas Aquinas gives us yet a third reason. He says that the baptism of the Lord points to our Christian sacrament of baptism. The baptism of St. John the Baptist was merely symbolic. It was a way to publicly profess one’s commitment to conversion and repentance. It did not actually forgive sin or make one a member of the family of God like our sacrament of baptism does. But, when Jesus received the baptism of John, He “consecrated it” so to speak, just as His presence at the wedding feast of Cana is seen as God’s blessing over matrimony.
In other words, when the baptism of John is imbued with the presence of Christ, it becomes what we celebrate today, and in the baptism of Jesus we see glimpses of our sacrament. The water signifies the cleansing that takes place. The descent of the dove signifies the reception of grace and the gifts of the Holy Spirit. The divine voice -- which cries out, “This is my beloved son, in whom I am well pleased” -- signifies our adoption as beloved sons (or daughters) of God.
For more on the sacrament of baptism, see my previous blog posts:
- On the Washing of Regeneration
- On Necessity and Wetness: Parts One -- Two -- Three
- Is Baptism Necessary for Salvation [an incomplete debate]: Parts One -- Two
- Eight Key Points, Part 5: Infant Baptism
- Repent, and Do What?
- On Baptism by Immersion
- Baptism: Empty Ritual or Saving Power?
Happy Solemnity of the Baptism of the Lord, which concludes the Christmas season.