Chandogya Upanishad 7.6

1. ‘Meditation (_dhyāna_), assuredly, is more than Thought. The earth meditates, as it were (_iva_). The atmosphere meditates, as it were. The heaven meditates, as it were. Water meditates, as it were. Mountains meditate, as it were. Gods and men meditate, as it were. Therefore whoever among men here attain greatness—they have, as it were, a part of the reward of meditation. Now, those who are small are quarrelers, tale-bearers, slanderers. But those who are superior—they have, as it were, a part of the reward of Meditation. Reverence Meditation.

2. He who reverences Meditation as Brahma—as far as Meditation goes, so far he has unlimited freedom, he who reverences Meditation as Brahma.’ ‘Is there, Sir, more than Meditation?’ ‘There is, assuredly, more than Meditation.’ ‘Do you, Sir, tell me it.’