ŚVETĀŚVATARA UPANISHAD · 4.8

ऋचो अक्षरे परमे व्योमन् यस्मिन् देवा अधि विश्वे निषेधुः ।
यस् तन् न वेद किम् ऋचा करिष्यति य इत् तद् विदुस् त इमे समासते ॥

ṛco akṣare parame vyoman yasmin devā adhi viśve niṣedhuḥ ।
yas tan na veda kim ṛcā kariṣyati ya it tad vidus ta ime samāsate ॥

He who does not know that indestructible being of the Rig-Veda, that highest ether-like (Self) wherein all the gods reside, of what use is the Rig-Veda to him? Those only who know it, rest contented.

F. Max Müller · The Upanishads, Sacred Books of the East 15 (1884)