John Lightfoot on Luke 11:36

[The whole shall be full of light.] This clause seems so much the same with the former, as if there were something of tautology; If thy whole body therefore be full of light, &c. Our Saviour speaketh of the eye, after the manner of the schools, where the evil eye, or the eye not single, signified the covetous, envious, and malicious mind: "Do not bring such a mind along with thee, but a candid, benign, gentle mind; then thou wilt be all bright and clear thyself, and all things will be bright and clear to thee. If you had but such a mind, O ye carping, blasphemous Jews, you would not frame so sordid and infamous a judgment of my miracles; but you would have a clear and candid opinion concerning them."