Kauṣītaki Upaniṣad 3.1.3

3.1.3

phalamuktāmṛtatvopāsanasya phalamāha, āpnotyamṛtatvamakṣitiṃ svarge loke'kṣayamamṛtatvaṃ spaṣṭamanyat | pratarddanaḥ prāṇaśabdaṃ śrutvā prāṇānāmindriyāṇāmekatvaṃ svayamavagataṃ prasaṅgāt pṛcchati, tat tatra prāṇānāmanekatve sati ha kila eke kecidvidvāṃsa āhuḥ kathayanti, ekabhūyaṃ vai ekabhāvameva prāṇā indriyāṇi gacchanti syuḥ, ityanena prakāreṇāhurityanvayaḥ | prāṇānāmekabhāve upapattiṃ yāṃ kathayanti tāmāha, na hi kaścana śaknuyāt hi yasmāt ko'pi na śaknuyāt sakṛdekavāraṃ yugapadityarthaḥ, vācā nāma prajñāpayituṃ cakṣuṣā rūpaṃ śrotreṇa śabdaṃ, vāgindriyeṇa nāma vaktumiti śeṣaḥ, prajñāpayituṃ avagamayitumavagantumiti yāvat, etaccakṣuḥśrotrābhyāṃ sambadhyate spaṣṭamanyat, manasā dhyātuṃ manasā dhyānaṃ kartumityanena prakāreṇa ekakāle vyāprārābhāvena ekabhūyaṃ vai prāṇāḥ vyākhyātaṃ, punarabhidhānaṃ nigamanārthaṃ | uktaṃ hetuṃ vivṛṇoti, ekaikaṃ rūparasādikaṃ sarvāṇyeva nikhilāni, ekaikamevetyanena sambadhyate, spaṣṭamanyat, etāni prajñāpayanti prakarṣeṇa niṣpādayanti gamayanti ca | ekaikameva