The baptism of Jesus is a crucial event in the inauguration of his earthly ministry, and a moment that reveals his deity, the participation of all three persons of the Trinity, and especially his purpose in coming to the Earth. In the account in Matthew’s gospel, Jesus tells John the Baptist to with the baptism of repentance, even though Jesus has no need to repent. He does it, so that all righteousness will be fulfilled. As the new Adam, he is careful to be fully obedient to all commands and ordinances of God. This makes him worthy in his humanity to substitute for us in atoning with the father in that sense. It is literally a matter of life and death.