Now when all the people were baptized, and when Jesus also had been baptized and was praying, the heaven was opened, and the Holy Spirit descended upon him in bodily form like a dove. And a voice came from heaven, “You are my Son, the Beloved; with you I am well pleased.”

In Jesus’ Baptism, God the Father testifies that Jesus is His Son in the presence of God the Holy Spirit in the form of a dove.  This is not to say that their relationship is altered in His Baptism, rather the Father is bearing witness to the identity of Jesus.  Luke establishes Jesus’ identity in the first few chapters of his Gospel:  Gabriel announces that He “will be called the Son of the Most High.”  Jesus responds to Mary and Joseph’s questioning when they left Him in Jerusalem, “Did you not know that I must be in my Father’s house?”  Following the story of Jesus’ baptism is the genealogy that ends with, “the Son of God.”  Following this is the temptation in the wilderness where the repeated question of Satan is, “If you are the Son of God…” Next is Jesus’ preaching in the synagogue in Nazareth where the amazed people ask, “Is not this Joseph’s son?”  Immediately following are two exorcism stories in which the demons recognize Him as the “Holy One of God” and “the Son of God.”  Jesus’ Baptism is God’s explicit claim on Jesus as His Son.  Following the claim, all of creation; angels, Satan, demons and humans question, test and affirm Jesus’ identity.  Jesus’ Baptism is also his identification with us.  “Jesus freely identified himself with the people.  For if her were not one of the people, he would not have come with the people for John’s baptism.”  (Chrystostom, Gospel of Matthew, Homily12.2)  In Jesus’ baptism, the water of our own baptism was sanctified.  As the water flowed over the Lord’s Holy and Divine body, it was blessed and sanctified.  In our baptism, this consecrated water cleanses us and unites us with the living Christ who identifies with us.  (Romans 6:4 and Col. 2:12)Our baptism is a sign of God’s covenant with us.  Just as circumcision was the sign of entrance into the Covenant Community in the Old Testament, Baptism marks our rebirth into the Church.  “In Him you were also circumcised with the circumcision made without hands, by putting off the body of the sins of the flesh, by the circumcision of Christ,buried with Him in baptism, in which you also were raised with Him through faith in the working of God, who raised Him from the dead.” (Colossians 2:11-12)  In Baptism God seals a covenant with us and adopts us as His sons and daughters.  He pours out His Spirit upon us, the “Spirit of adoption” the Spirit who is the “first installment.” (Romans 8:15 and II Corinthians 1:21)  We receive this covenant of Grace through faith, which is itself a gift of God.  (Confession of Faith, 4.09)
God’s covenants and promises are forever. We can be assured of our salvation because of the covenant promises sealed in our baptism and reaffirmed each time we eat the Lord’s Supper.  Our confidence in eternal life is not based on our understanding or faith, but rather on the promises of God in “water and the spirit.”  (John 3:5)

Our baptism also unites us with all the Baptized throughout time and space.  Not because we have a unity of our own, but we all share the common union with Christ.  Through our union with Christ we share a derivative unity with each other.  We are one in Christ through our baptismal covenant, even though the church is divided we share a real bond that is stronger than our divisions; we may deny fellowship with one another but we cannot deny the relationship that exists in Christ.