Why does baptism matter? Jesus instructs us to be baptized and set the example by being baptized. (Matthew 28:19-20, Mark 1:9)
Obedience to Jesus shows we believe and follow Him. (1 John 2:3) Because Jesus went public about His love for us, we can go public about our love for Him. Being baptized shows both to ourselves and to others that we have turned away from doing life our own way, and instead desire to live for God.