“The true light that gives light to everyone was coming into the world.” (John 1:9 NIV)
God has sent many prophets in the past, but none of them is like Jesus. While other men are messengers, reflecting, as it were, a small part of the light of God, Jesus was different. He did not simply reflect God’s light. Since He is God He is the source of light.
The light of Jesus shines on all men. That is to say, it reveals all men as what they are, sinners (John 3:19-20). But it also reveals the true children of God who have repented of their sins and have been transformed by the power of God.