"This is He of whom I said, 'After me comes a Man who is preferred before me, for He was before me.' I did not know Him; but that He should be revealed to Israel, therefore I came baptizing with water. And John bore witness, saying, "I saw the Spirit descending from heaven like a dove, and He remained upon Him. I did not know Him, but He who sent me to baptize with water said to me, 'Upon whom you see the Spirit descending, and remaining on Him, this is He who baptizes with the Holy Spirit.' And I have seen and testified that this is the Son of God."
"This is He of whom I said, 'After me comes a Man who is preferred before me, for He was before me.' I did not know Him; but that He should be revealed to Israel, therefore I came baptizing with water." John the Baptist immediately assured his disciples and those who had come to be baptized, that Jesus - the Lamb of God - was not a new and unanticipated figure; but was that same person whom John had already spoken of as the greater One, who would follow only chronologically.
I did not know Him; but that He should be revealed to Israel, therefore I came baptizing with water. Now John offers the fundamental answer to the question, "Why then do you baptize if you are not the Christ, nor Elijah, nor the Prophet?" Everything about John's baptism was designed to point men to the future work of Christ. We have discussed previously the Baptist's call to a heartfelt repentance and the symbolic washing of the body - representative of the cleansing of the conscience, soul, and spirit which Jesus would accomplish through the blood of His cross. But John would now impart to his hearers a direct word from the Lord, given specifically to identify the Christ; and this sign was reserved for the moment when Christ Himself would be baptized by John.
And John bore witness, saying, "I saw the Spirit descending from heaven like a dove, and He remained upon Him. I did not know Him, but He who sent me to baptize with water said to me, 'Upon whom you see the Spirit descending, and remaining on Him, this is He who baptizes with the Holy Spirit.'"
For the sake of contrast, let us consider how the Spirit descended upon Jesus' disciples after He had ascended to the right hand of the Father. And suddenly there came a sound from heaven, as of a rushing mighty wind, and it filled the whole house where they were sitting. Then there appeared to them divided tongues, as of fire, and one sat upon each of them. - Acts 2:2,3 It is common among converts to Christianity for their first encounter with the Holy Spirit to be one of conviction; as the refining fire which condemns sin in the flesh purifies the the sin-infected soul. This is a necessary action in preparation for the reception of God's perfect peace and joy and love, which then find a suitable heart in which to abide.
Yet John saw the Spirit descend upon Jesus as a dove, the symbol of peace. The Spirit was not a new revelation to Jesus. Because Jesus was one with the Father and the Spirit from the beginning, the peace of God had always abided with Him. And no cleansing action was necessary because Jesus was without sin; as Peter affirms, " . . you were not redeemed with corruptible things, like silver or gold, from your aimless conduct received by tradition from your fathers, but with the precious blood of Christ, as of a lamb without blemish and without spot." - 1st Peter 1:18,19
Also, the Spirit remained upon Jesus; once again, in contrast with the Disciples. The Book of Acts describes how the Apostles and deacons would gather together and pray to be filled, and re-filled, with the Holy Spirit. Luke's account of the early Church records how Peter and others would be filled with the Spirit in order to speak boldly and to work miracles. But the Spirit remained upon Jesus for the entirety of His earthly ministry.
"And I have seen and testified that this is the Son of God."
Inherent within the act of water baptism which John was sent to perform was a pre-ordained sign by which John would recognize the Messiah. God had spoken to John in advance so that there could be no doubt involved in this proclamation; the most profound act of his prophetic calling. John had been chosen, prepared, and instructed, in order to give his solemn certification that Jesus was indeed the true and only Christ, the Son of God.
After following Jesus for three years and then witnessing the resurrection with their own eyes, the Apostles addressed the people of Jerusalem re-affirming the Baptist's certification of Christ, and offering a new baptism unto eternal life:
"Men of Israel, hear these words: Jesus of Nazareth, a Man attested by God to you by miracles, wonders, and signs which God did through Him in your midst, as you yourselves also know - Him, being delivered by the determined purpose and foreknowledge of God, you have taken by lawless hands, have crucified, and put to death; whom God raised up, having loosed the pains of death, because it was not possible that He should be held by it. . . "
" . . This Jesus God has raised up, of which we are all witnesses. Therefore being exalted to the right hand of God, and having received from the Father the promise of the Holy Spirit, He poured out this which you now see and hear. "For David did not ascend into the heavens, but he says himself:
The Lord said to my Lord,
'Sit at My right hand,
Till I make Your enemies Your footstool.'
'Sit at My right hand,
Till I make Your enemies Your footstool.'
"Therefore let all the house of Israel know assuredly that God has made this Jesus, whom you crucified, both Lord and Christ."
Now when they heard this, they were cut to the heart, and said to Peter and the rest of the apostles, "Men and brethren, what shall we do?"
Then Peter said to them, "Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins; and you shall receive the gift of the Holy Spirit." - Excerpts from the second chapter of Acts