Muṇḍaka Upaniṣad 2.1.10

2.1.10

puruṣa evedaṃ viśvaṃ karma tapo brahma parāmṛtam.
etad yo veda nihitaṃ guhāyāṃ so 'vidyāgranthiṃ vikiratīha somya.

10. The Person (Purusha) himself is everything here:
Work (_karman_) and austerity (_tapas_) and Brahma, beyond death.
He who knows That, set in the secret place [of the heart]—
He here on earth, my friend, rends asunder the knot of ignorance.