1. To follow the example set by Jesus.

"At that time Jesus came from Nazareth and was baptized by John in the river."
Mark 1:9

2. Because Jesus commanded it.

"Jesus said, 'Go then, to all people everywhere and make them my disciples, baptize them in the name of the Father, the Son, and the Holy Spirit, and then teach them to obey everything I have commanded you.'"
Matt. 28:19-20

3. It demonstrates that I really am a believer.

"...many of the people who heard Him believed and were baptized ."
Acts 18:8

4. Because obeying Jesus' command shows you know Him.

"We know that we have come to know Him, if we obey His commands."
1 John 2:3