Matthew 6:23

but if your eyesight is bad, your whole body will be dark. If however the very light within you is darkness, how dense must the darkness be!

Luke 11:34-35

The lamp of the body is the eye. When your eyesight is good, your whole body also is lighted up; but when it is defective, your body is darkened.

Ephesians 5:8

There was a time when you were nothing but darkness. Now, as Christians, you are Light itself.

Treasury of Scripture Knowledge

Summary

Then I saw that wisdom excelleth folly, as far as light excelleth darkness.

Bible References

Light

Matthew 6:23
but if your eyesight is bad, your whole body will be dark. If however the very light within you is darkness, how dense must the darkness be!
Luke 11:34
The lamp of the body is the eye. When your eyesight is good, your whole body also is lighted up; but when it is defective, your body is darkened.
Ephesians 5:8
There was a time when you were nothing but darkness. Now, as Christians, you are Light itself.