Single Eyes
The eye is the lamp of the body; so then if your eye is clear, your whole body will be full of light. But if your eye is bad, your whole body will be full of darkness. If then the light that is in you is darkness, how great is the darkness!
Matthew 6:22-23
The eye is the lamp of your body; when your eye is clear, your whole body also is full of light; but when it is bad, your body also is full of darkness. Then watch out that the light in you is not darkness. If therefore your whole body is full of light, with no dark part in it, it will be wholly illumined, as when the lamp illumines you with its rays.
Luke 11:34-36
The teaching of the Kingdom is a simple thing. It is, actually, the smallest of all seeds, even though it produces the biggest plant.
You could put a whole lot of effort into studying the teachings of Jesus, and cataloging them, and indeed, many have, and many of these works have been profitable. However, whether they are understood and lived is an entirely different matter.