Chapter 15 · verse 14 · gita.yoga.org

Bhagavad Gita 15.14

अहं वैश्वानरो भूत्वा प्राणिनां देहमाश्रितः।प्राणापानसमायुक्तः पचाम्यन्नं चतुर्विधम्

Having become the fire Vaisvanara, I abide in the bodies of living beings and, associated with the Prana and the Apana, digest the fourfold food.