Our bodies also need light to remain healthy. It lets us see into the distance in order to make good decisions. A flashlight or a candle in the darkness of night or deep in a cave keeps us safe. A street light provides protection for pedestrians and traffic alike. In climates where the sun doesn't shine much during the winter there are many cases of depression among the population.
Light is essential for the earth, for all creation.
No wonder, then, that God is often described as light in Holy Scripture. Human beings long for the light. We have been created to need it physically and emotionally. Our God loves us and wants to be close to us. God wants us to live in God's light of truth.