Chandogya Upanishad 7.2

'Speech is better than a name. Speech makes us understand the Rig-veda, Yagur-veda, Sâma-veda, and as the fourth the Âtharvana, as the fifth the Itihâsa-purâna, the Veda of the Vedas, the Pitrya, the Râsi, the Daiva, the Nidhi, the Vâkovâkya, the Ekâyana, the Deva-vidyâ, the Brahma-vidyâ, the Kshatra-vidyâ, the Nakshatra-vidyâ, the Sarpa and Devagana-vidyâ; heaven, earth, air, ether, water, fire, gods, men, cattle, birds, herbs, trees, all beasts down to worms, midges, and ants; what is right and what is wrong; what is true and what is false; what is good and what is bad; what is pleasing and what is not pleasing. For if there were no speech, neither right nor wrong would be known, neither the true nor the false, neither the good nor the bad, neither the pleasant nor the unpleasant. Speech makes us understand all this. Meditate on speech.

'He who meditates on speech as Brahman, is, as it were, lord and master as far as speech reaches—he who meditates on speech as Brahman.' 'Sir, is there something better than speech?' 'Yes, there is something better than speech.' 'Sir, tell it me."