As Jesus comes to John the Baptist for Baptism, John tells Him 'I am the one that needs to be baptized by you'. Jesus tells John The Baptist 'It should be done, for we must carry out all that God requires'. Jesus had not sinned so he was not repenting but was humbling Himself to the will of The Father. To humble ourselves is to lower ourselves...or to elevate something else...in this instance, elevating God in our life.
Likewise, our Christian life is a life that should be humble. We are to humble ourselves to repent for our wrongs. We can humble ourselves to obey the way of God. Humbling ourselves to do something publicly to show our faith in God through Jesus. Jesus showed his humility as He was baptized and that baptism was the beginning of His Public Ministry...it should be our beginning as well.