Mt 3:13 Then Jesus came from Galilee to John at the Jordan to be baptized by him.
Mt 3:15 But Jesus answered and said to him, "Permit it to be so now, for thus it is fitting for us to fulfill all righteousness." Then he allowed Him.
To be sure, He was not baptized as a repentant sinner. He had no need to repent. He was the perfectly sinless One. The purpose of baptism is identification.
The waters of the Jordan represented judgment. As repentant sinners came to John for baptism, they were saying in effect: "I am a sinner who deserves to be judged. My baptism is the symbolic act of identifying myself with the Jordan river which represents judgment."
The Lord Jesus' baptism, on the other hand, served as a pledge of what He will do for them at the cross. He identified Himself with them as the one who will bore the just judgment that they deserved.
God has a righteous and just claim against man's sin. He demands justice and punishment which we truly deserved. The Lord Jesus' baptism was Him saying in effect: "I am identifying myself as the Sin-bearer of all men. I am taking up their judgment on Myself. God's righteous and just demand must be met and satisfied. Sin must be paid. And so, symbolically, through baptism, I am pledging Myself as the payment."
