The Spirit, descending like a dove on Jesus, enables him to do his work as Saviour. The dove is known as a sacrificial animal (for the poor people), and thus points to Jesus as the one who is going to sacrifice himself for sinful people. The Father speaks and makes it clear (by telling Jesus: You are my beloved Son
; a quote from Psalm 2:1–12) that he is very pleased about this baptism which shows that his only begotten Son is willing to die for sinful people.
10 And when he came up out of the water, immediately he saw the heavens being torn open and the Spirit descending on him like a dove.