This is the reason, to set up John as a witness:
John 1:
29The next day John saw Jesus coming toward him and said, “Look, the Lamb of God, who takes away the sin of the world!
30This is He of whom I said, ‘A man who comes after me has surpassed me because He was before me.’
31I myself did not know Him, but the reason I came baptizing with water was that He might be revealed to Israel.”
32Then John testified, “I saw the Spirit descending from heaven like a dove and resting on Him.
33I myself did not know Him,
but the One who sent me to baptize with water told me, ‘The man on whom you see the Spirit descend and rest is He who will baptize with the Holy Spirit.’ 34I have seen and testified that this is the Son of God.
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