Taittirīyopaniṣat 01.21
satyam iti satyavacā rāthītaraḥ। tapa iti taponityaḥ pauruśiṣṭiḥ। svādhyāya-pravacane eva iti nāko maudgalyaḥ। tad dhi tapas tad dhi tapaḥ ॥21॥
Satyavacā Rāthītaraḥ, one who always speaks truth, said, "satyam", i.e. "truth". Taponityaḥ Pauruśiṣṭiḥ, one who is always engaged in austerity, said, "tapah", i.e. "austerity". Nāka Maudgalyaḥ said, "study and imparting knowledge alone". That indeed is austerity, that indeed is austerity.
Taittirīya Bhāshya 01.21
Truthfulness, self-study, imparting knowledge, and chanting of Vedic hymns - all are austerities. But he who, having thoroughly understood Lord Viṣṇu, explains and repeatedly remembers him, gets liberated. For him, nothing remains to be done.
"satye tapasi vā cīrṇe sarvakarma kṛtaṃ bhavet। svādhyāye ca pravacane hyantarbhāvo viśeṣataḥ॥"
"When truth and austerity are practiced, all actions are considered accomplished. Especially when it includes self-study and imparting knowledge."
iti ca॥
- stated thus as well.
"yaṃ yaṃ kratum adhīte tena tenāsy eṣṭaṃ bhavati।"
"Whatever sacrifice one studies, that very thing becomes desired for him."
iti ca śrutiḥ।
- stated thus by a Vedic statement.
"japyenaiva tu saṁsiddhyet brāhmaṇo nātra-saṁśayaḥ। kuryād anyan na vā kuryāt maitro brāhmaṇa ucyate॥"
"A brāhmaṇa attains perfection solely through repeated chanting (of mantras), there is no doubt about this. Whether he performs other actions or not, he is still called a compassionate brāhmaṇa."
iti bhārate॥
- stated thus, in the Mahabhārata.
samyag jñātvā tu yo viṣṇuṃ vyākhyāyīta japeta ca। na tasya kiṃñcid akṛtaṃ kartavyaṃ mucyate ca saḥ॥
"But he who, having thoroughly understood Lord Viṣṇu, explains and repeatedly remembers, for him nothing remains to be done; he is liberated."
iti karmatatve।
- stated thus in Karmatatva (the principle of action) text.
