Upaniṣads · Bṛhadāraṇyaka 5.9

Bṛhadāraṇyaka 5.9.1

अयमग्निर्वैश्वानरो योऽयमन्तः पुरुषे ।
येनेदमन्नं पच्यते ।
यदिदमद्यते ।
तस्यैष घोषो भवति ।
यमेतत्कर्णावपिधाय शृणोति ।
स यदोत्क्रमिष्यन् भवति नैनं घोषं शृणोति ॥ ५.९.१ ॥

This Vaiśvānara fire which is within the person, by which this food is cooked and this which is eaten, its sound arises, which one hears with the ears closed. When he is about to depart, he does not hear this sound.