In this context it should not be forgotten that the dove, being a peaceful bird, is also the only bird that was included in the sacrificial service of the old covenant. Doves were caught in large numbers in the wilderness of Judah to be sold in Jerusalem. The dove is thus treated like the lamb. The Messiah will be a sacrificial lamb (Isaiah 53:7). John the Baptist sees the dove and the lamb on the same level (see John 1:29–36). Since the Spirit descends from heaven, God shows a figure from the sky, namely, the dove. From what follows it will become clear that the Spirit did indeed come upon Jesus to sacrifice him for the people, for the temptations follow immediately afterwards through the prompting of the Spirit (Mark 1:12).1
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.