Śatapatha Brāhmaṇa ("of a hundred paths") 13.3.8.4

13.3.8.4

atha yadyakṣyāmayo vindet sauryaṃ carumanunirvapetsūryo vai prajānāṃ cakṣuryadā hyevaiṣa udetyathedaṃ sarvaṃ carati cakṣuṣaivāsmiṃstaccakṣurdadhāti sa yaccarurbhavati cakṣuṣā hyayamātmā carati

And if an eye-disease were to befal it, let him in addition prepare a pap to Sûrya;--the Sun, doubtless, is the eye of creatures, for when he rises everything here moves: by means of the eye (of the world) he thus bestows the eye upon it. And as to why it is a pap (karu), it is because by means of the eye this self (body or mind) moves (kar).