Why must a believer in Jesus be baptized in water?

Now, when Jesus was baptized, God the Father spoke from Heaven and confirmed Jesus’ Sonship, and the Holy Spirit came down from Heaven and upon Jesus to commission and empower Him for a life of service to God the Father. All three persons of the Holy Trinity were present when Jesus was baptized: Himself, God the Father, and the Holy Spirit.

Interestingly, Jesus commanded His believers and followers to be baptized in the Name of the Father, of the Son, and of the Holy Spirit? Why? Because our baptism reflects Jesus’ baptism.