Exodus 13:20-22
After leaving Sukkoth the Israelites camped at Etham on the edge of the desert. By day the Lord went ahead of them in a pillar of cloud to guide them on their way and by night in a pillar of fire to give them light, so that they could travel by day or night. Neither the pillar of cloud by day nor the pillar of fire by night left its place in front of the people.

 John 8:12
When Jesus spoke again to the people, he said, 
I am the light of the world. 
Whoever follows me will never walk in darkness, but will have the light of life.

Light of the world
You stepped down into darkness
Opened my eyes, let me see
Beauty that made this heart adore You
Hope of a life spent with You

Here I am to worship
Here I am to bow down
Here I am to say that You’re my God

You’re altogether lovely
Altogether worthy
Altogether wonderful to me