And it came to pass in those days, that Jesus came from Nazareth of Galilee, and was baptized of John in Jordan. And straightway coming up out of the water, He saw the heavens opened, and the Spirit like a dove descending upon Him: and there came a voice from heaven, saying, “Thou art My beloved Son, in whom I am well pleased.” Mark 1:9-11
To fulfill the will of God the Father Jesus presented Himself to John the Baptizer for baptism, to fulfill righteousness (Matthew 3:15), and upon doing so fitted Himself to the service and will of the Father.
The Father speaks from heaven His approval of His Son, “You are My beloved Son, in whom I am well pleased.” It is a command from God that when we come to faith in Jesus Christ, we testify of our faith by way of baptism showing His death, burial and resurrection by immersion. The submerging of the whole body under water; a testimony to others of our faith in Him. If you fail in obedience to baptism, you will fail in your faithfulness to Him.
Believe the voice of the Father concerning the Son. Believe the voice of Jesus that He and the Father are One (John 10:30).