On a Sabbath, the disciples asked Jesus whether a certain beggar was blind because of his parents' sin or his own sin. The disciples were assuming that an affliction was a punishment from God for sin (Deuteronomy 28:20-21). Jesus' reply (9:3) denied the essential connection between personal or parental sin and affliction or suffering; as a result of this man's affliction, God's power would be revealed. Jesus then referred not only to his work in the world on behalf of his Father but to his approaching death which would bring to an end his earthly ministry (9:4). He then repeated the 'I AM' saying of 8: 12 before demonstrating it through the sixth sign, the giving of sight to a beggar who had never been able to see, having been born blind. Giving sight to the blind was a Messianic act (Isaiah 35:5).

His action in 9:6 may be understood in a similar way to those described in Mark 7:32-33, when Jesus healed the deaf and dumb man. The blind beggar could not see Jesus but the physical rubbing of his eyes made it clear to him that the darkness in which he had always lived was about to be removed for the first time in his life. Someone who has never seen light needs to be prepared for the dazzling shock of it, when the darkness is removed. After Jesus had rubbed the man's eyes, he told him to go and wash them in the well-known pool of Siloam in Jerusalem. The man, still blind, obeyed and found that he could see (9:7). This caused astonishment amongst those who knew him (9:8-10).

He knew that a man called Jesus had done this for him but he had not yet seen Jesus and did not know which man he was, 9: 11-12.