“No longer will you need the sun to shine by day,
nor the moon to give its light by night,
for the LORD your God will be your everlasting light,
and your God will be your glory.
Your sun will never set; your moon will not go down.
For the LORD will be your everlasting light.
Your days of mourning will come to an end.
Isaiah 60:19-20 (NLT)
 

The Lord is my light and my salvation;
    whom shall I fear?
The Lord is the stronghold of my life;
    of whom shall I be afraid?
Psalm 27:1 (ESV)

“You are the light of the world—like a city on a hilltop that cannot be hidden. No one lights a lamp and then puts it under a basket. Instead, a lamp is placed on a stand, where it gives light to everyone in the house. In the same way, let your good deeds shine out for all to see, so that everyone will praise your heavenly Father."
Matthew 5:14-16

For once you were full of darkness, but now you have light from the Lord. So live as people of light! For this light within you produces only what is good and right and true. Carefully determine what pleases the Lord. Take no part in the worthless deeds of evil and darkness; instead, expose them. 
Ephesians 5:8-11