MUṆḌAKA UPANISHAD · 1.1.3

शौनको ह वै महाशालोऽङ्गिरसं विधिवदुपसन्नः पप्रच्छ ।
कस्मिन्नु भगवो विज्ञाते सर्वमिदं विज्ञातं भवतीति ॥ ३॥

śaunako ha vai mahāśālo’ṅgirasaṃ vidhivadupasannaḥ papraccha ।
kasminnu bhagavo vijñāte sarvamidaṃ vijñātaṃ bhavatīti ॥ 3॥

Shaunaka, the great house-lord, came to Angiras in the due way of the disciple and asked of him, “Lord, by knowing what does all this that is become known?”