Baptism is the profession of your faith to do God's will. It is an all-important act that marks the beginning of your reconciliation with God through your sincere repentance. But the belief that baptism is for the repentance of sins is not true. To REPENT is to TURN AROUND. So, the true purpose of baptism is not to turn around from sins but, to turn around from one life to another. It is the circumcision of one's heart, and for us sinners, it means to turn around from a life of DISOBEDIENCE to a life of OBEDIENCE to God. 

As for the Lord Jesus Christ, when it was time for him to come out into the world (Heb 10:5) to begin his work, Christ needed to set things right (Mat 3:15), as willed by the Father. He had to first enter into a Covenant with God, on his baptism, to profess his faith in the Father's will that he shall rest from his own will (Heb 4:10); that he shall turn around from a secular life, to begin a life devoted to the work of proclaiming the Good News (Heb 10:7,9). That was the reason Jesus had to be baptized. As a token of the Father's approval, God gave Jesus Christ the holy spirit (Mat 3:16-17; Lu 4:18).

Once you have covenanted with God in your baptism, to turn around from your old life to the new, there is no shrinking back, like the dog that has returned to its vomit (2Pe 2:20-22), lest you draw back to perdition (Heb 10:38-39) for exposing Christ to shame by crucifying him all over again (Heb 6:4-6).

Just as your Lord had fulfilled his covenant with the Father, so must you, if indeed, you are a true disciple of Christ and a child of the Most High God.

Blessed are those who have been given wisdom to discern between truth and lie.