As Jesus is baptized and praying, heaven is opened. The Holy Spirit descends on him in bodily form like a dove. A voice from heaven says, “You are my beloved Son; with you I am well pleased” (Luke 3:21–22).
Luke briefly places Jesus’ baptism alongside the baptism of “all the people” and then slows down to describe what happens as Jesus prays. The sky opens, the Holy Spirit comes down in a visible, bodily way “like a dove,” and a voice speaks from the sky. The voice directly addresses Jesus, calling him the beloved Son and expressing pleasure in him. This scene comes at the close of John the Baptist’s public ministry and just before Luke turns to Jesus’ family line and then his testing in the wilderness (Luke 3:1–20; Luke 3:23–38; Luke 4:1–13).
Luke presents Jesus’ baptism as part of a public moment (“all the people”), but then highlights what singles Jesus out: while he is praying, the sky opens, the Holy Spirit comes down on him in a visible, bodily way “like a dove,” and a voice from the sky addresses him as God’s beloved Son and expresses approval (Luke 3:21–22).
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Luke 3:21-22, then read the surrounding section so the answer stays connected to the passage's flow.
21Now it happened, when all the people were baptized, that, Jesus also having been baptized, and praying, the sky was opened,
22and the Holy Spirit descended in a bodily form, as a dove, on him, and a voice came out of the sky, saying "You are my beloved Son. In you I am well pleased."