Shat.Upa 03.04

पायूपस्थेपानं चक्षुःश्रोत्रे मुखनासिकाभ्यां प्राणः स्वयं प्रतिष्ठते। मध्ये तु समानः। एष ह्येतद्धुतमन्नं समं नयति तस्मादेताः सप्तार्चिषो भवन्ति। हृदि ह्येष आत्मा ॥४॥

pāyūpathe pānaṃ cakṣuḥśrotre mukhanāsikābhyāṃ prāṇaḥ svayaṃ pratiṣṭhate। madhye tu samānaḥ। eṣa hyetaddhutamannaṃ samaṃ nayati tasmādetāḥ saptārciṣo bhavanti। hṛdi hyeṣa ātmā ॥4॥

[पायूपस्थे (pāyūpathe) - in the path of the rectum; पानं (pānaṃ) - drinking; चक्षुः (cakṣuḥ) - eyes; श्रोत्रे (śrotre) - ears; मुखनासिकाभ्यां (mukhanāsikābhyāṃ) - through the mouth and nose; प्राणः (prāṇaḥ) - the vital breath; स्वयं (svayaṃ) - by itself; प्रतिष्ठते (pratiṣṭhate) - is established; मध्ये (madhye) - in the middle; तु (tu) - but; समानः (samānaḥ) - the equalizing breath; एषः (eṣaḥ) - this; हि (hi) - indeed; एतत् (etat) - this; हुतम् (hutam) - offered; अन्नम् (annam) - food; समम् (samam) - equally; नयति (nayati) - leads; तस्मात् (tasmāt) - therefore; एताः (etāḥ) - these; सप्त (sapta) - seven; अर्चिषः (arciṣaḥ) - flames; भवन्ति (bhavanti) - become; हृदि (hṛdi) - in the heart; हि (hi) - indeed; एषः (eṣaḥ) - this; आत्मा (ātmā) - ātmān;]

The vital breath is established by itself in the path of the rectum, drinking, eyes, ears, and through the mouth and nose. But in the middle is the equalizing breath, which leads the offered food equally. Therefore, these become the seven flames. Indeed, this is the Ātman residing in the heart.