God sent a man, John the Baptist, to tell about the light so that everyone might believe because of his testimony. John himself was not the light; he was simply a witness to tell about the lights. The one who is the true light, who gives light to everyone, was coming into the world. John testified about him when he shouted to the crowds, "This is the one I was talking about when I said, 'Someone is coming after me who is far greater than I am, for he existed long before me.' "
This was John's testimony when the Jewish leaders sent priests and Temple assistants from Jerusalem to ask John, "Who are you?" He came right out and said, "I am not the Messiah." John replied in the words of the prophet Isaiah: "I am a voice shouting in the wilderness, 'Clear the way for the Lord's coming!' "
John told them, "I baptize with water, but right here in the crowd is someone you do not recognize. Though his ministry follows mine, I'm not ever worthy to be his slave and untie the straps of his sandal."
The next day John saw Jesus coming toward him and said, "Look! The lamb of God who takes away the sin of the world! He is the one I was talking about when I said, "A man is coming after me who is far greater than I am, for he existed long before me." Then John testified, "I saw the Holy Spirit descending like a dove from heaven and resting upon him. I saw this happen to Jesus, so I testify that he is the Chosen One of God."
The following day John was again standing with two of his disciples. As jesus walked by, John looked at him and declared, "Look! There is the lamb of God!" When John's two disciples heard this, they followed Jesus.