I am the light of the world. Jesus was speaking this during the feast of tabernacles, when the women’s court in the temple was lighted by giant lamps. This reminded the people of how God was with them in the wilderness guiding them by a pillar of fire by night. Jesus was saying that He is the light come from God, “the” light, not just “a” light or “another” light among many (John 1:9). The only people who cannot see the light are blind people (2 Corinthians 4:4).
The Pharisees objected to Christ’s testimony because all testimonies must be proven by two witnesses according to the law (Deuteronomy 17:6). They did not understand that He did have two witnesses; Himself and His Father. Jesus made it clear that their thinking was not dependable because their judgment was faulty. If the law required two human witnesses for accuracy, how much more dependable were two divine persons, the Father and the Son?
These Jewish experts claimed to know the law of God, but they did not know the God of the law. They did not know the Father, so they did not know the Son, and therefore they walked in darkness. They thought they had the light, the light of Moses, but they failed to understand that Moses’ light was pointing to Jesus (Luke 24:26-27, 45-48 / John 5:46).
For Christians it is comforting to know that we will never have to walk through the dark times in life without Jesus lighting our way (Psalm 119:105 / Proverbs 4:18). It is when we refuse to follow the light that we find ourselves in darkness, but we find renewed fellowship when we turn back to the light (1 John 1:5-10).
How do we live up to the light we have been given (Ephesians 5:8)? By walking as those who are right now exposed to the light (Matthew 5:16 / Romans 13:12 / Philippians 2:15).
This is about right now: the light is not shining through us if it is not shining to us.