Chandogya Upanishad 4.8.4

4.8.4

sa ya etam evaṃ vidvāṃś catuṣkalaṃ pādaṃ brahmaṇa āyatanavān ity upāsta āyatanavān asmiṃl loke bhavati \
āyatanavato ha lokāñ jayati ya etam evaṃ vidvāṃś catuṣkalaṃ pādaṃ brahmaṇa āyatanavān ity upāste \\408.4\

3. ‘Let me tell you, my dear, a quarter of Brahma.’ ‘Tell me, Sir.’ To him it then said: ‘One sixteenth is breath. One sixteenth is the eye. One sixteenth is the ear. One sixteenth is mind. This, verily, my dear, is the quarter of Brahma, consisting of four sixteenths, named Possessing-a-support. 4. He who, knowing it thus, reverences a quarter of Brahma, consisting of four sixteenths, as Possessing-a-support, comes to possess a support in this world. Then he wins worlds possessing a support who, knowing it thus, reverences a quarter of Brahma, consisting of four sixteenths, as Possessing-a-support.’