Kaṭha Upaniṣad 35

35

idaṃ śruter vacanam / lokādiṃ lokānām ādiṃ pratham aśarīritvād agniṃ taṃ prakṛtaṃ naciketasā prārthitam uvācoktavān mṛtyus tasmai naciketase / kiñ ca yā iṣṭakāś cetavyāḥ svarūpeṇa, yāvatīr vā saṅkhyayā, yathā vā ciyate 'gnir yena prakāreṇa sarvam etad uktavān ity arthaḥ / sa cāpi naciketās tan mṛtyunoktaṃ pratyavadad yathāvat pratyayenāvadat pratyuccāritavān / athāsya pratyuccāraṇena tuṣṭaḥ san mṛtyuḥ punar evāha varatrayavyatirekeṇānyaṃ varaṃ ditsuḥ ///1,1.15 //

Shankara’s Commentary:
Com.—This, the Sruti itself says. Death explained o Nachiketas, the fire, which was the source of the worlds, being the first embodied existence, the same that was asked for by Nachiketas; again he told him of what form the sacrificial bricks were to be, how many in number and in what manner the sacrificial fire was to be lit and all this; Nachiketas also faithfully repeated what was told him by Death. Then delighted by his repetition, Death said to him again inclined to grant him a boon other than the three promised.