By baptizing Jesus, John was declaring to all that here was the one they had been waiting for, the Son of God. Also showed that Jesus identified with sinners. His baptism symbolized the sinners’ baptism into the righteousness of Christ, in addition, Jesus coming to John showed His approval of John's baptism, bearing witness to it, that it was from heaven and approved by God. This would be important in the future when others would begin to doubt John’s authority, particularly after his arrest by Herod.