Chandogya Upanishad 7.16

7.16.1

eṣa tu vā ativadati yaḥ satyenātivadati \
so 'haṃ bhagavaḥ satyenātivadānīti \
satyaṃ tv eva vijijñāsitavyam iti \
satyaṃ bhagavo vijijñāsa iti \\716.1\

सत्येन with truth अतिवदानि would speak surpassingly इति. (Sanatkumāra) सत्यम् the truth एव itself तु but (therefore) विजिज्ञासितव्यम् one must desire to under-stand इति. (Nārada) भगवः revered sir सत्यम् the truth विजिज्ञासे I desire to understand इति.

‘But he really speaks surpassingly who speaks surpassingly with truth.’ ‘Revered sir, being such, I would speak surpassingly with truth.’ ‘But one must desire to understand the truth.’ ‘Revered sir, I desire to understand the truth.’