"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)."
--Benedict XVI, Jesus of Nazareth--Part One: From the Baptism in the Jordan to the Transfiguration (New York: Doubleday, 2007), p. 18