Hilary of Poitiers

Otherwise; from the office of the light of the eye, He calls it the light of the heart; which if it continue single and brilliant, will confer on the body the brightness of the eternal light, and pour again into the corrupted flesh the splendor of its origin, that is, in the resurrection. But if it be obscured by sin, and evil in will, the bodily nature will yet abide subject to all the evils of the understanding.