John the Baptizer announced that Jesus was the one who would become a sacrifice to remove guilt for sin, and how God had confirmed that Jesus was the Son of God.

John 1:29-34

29 The next day John saw Jesus coming toward him. He said to the people, “Look! Here is the man whom God has appointed to be a sacrifice [MET], like the lambs that the people of Israel sacrificed! By sacrificing himself he will make it possible for everyone in the world to be no longer guilty for having sinned. 30 He is the one about whom I said before, ‘Someone will come later who is more important than I am, since he existed long before me.’ 31 I myself did not previously recognize that he was the Messiah. But now I know who he is, and I have baptized people with water to enable you people of Israel to recognize who he is.”

32 John spoke clearly what God had shown him about Jesus. He said, “I saw God’s Spirit as he was descending from heaven in the form of a dove. The Spirit remained on Jesus. 33 I myself did not know previously that he was the Messiah. However, God sent me to baptize people with water, people who said they wanted to turn from their sinful ways. While I was doing that, God told me, ‘The man on whom you will see my Spirit descend and remain is the one who will put the Holy Spirit within you (pl) to truly change your lives.’ 34 I saw the Spirit descend on him, and I tell you that he is ◄the Son of God/the person who is both God and man►.”