Matthew 6:22 in the King James Version
The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light.
Context
21 for where your treasure is, there your heart will be also.
22 “The lamp of the body is the eye. If therefore your eye is sound, your whole body will be full of light.
23 But if your eye is evil, your whole body will be full of darkness. If therefore the light that is in you is darkness, how great is the darkness!