Bhashya
अयमनिवैश्वानरः, पूर्ववदुपासनान्तरम्; अयम् अग्निः वैश्वानरः; कोऽयमग्निरित्याह—योऽयमन्तः पुरुषे ।किं शरीरारम्भकः? नेत्युच्यते—येन अग्निना वैश्वानराख्येन इदमन्नं पच्यते ।किं तदन्नम्? यदिदमद्यते भुज्यते अन्नं प्रजाभिः, जाठरोऽग्निरित्यर्थः ।तस्य साक्षादुपलक्षणार्थमिदमाह—तस्याग्नेः अन्नं पचतः जाठरस्य एष घोषो भवति; कोऽसौ? यं घोषम्, एतदिति क्रियाविशेषणम्, कर्णावपिधाय अङ्गुलीभ्यामपिधानं कृत्वा शृणोति ।तं प्रजापतिमुपासीत वैश्वानरमग्निम् ।अत्रापि ताद्भाव्यं फलम् ।तत्र प्रासङ्गिकमिदमरिष्टलक्षणमुच्यते— सोऽत्र शरीरे भोक्ता यदा उत्क्रमिष्यन्भवति, नैनं घोषं शृणोति ॥
In plain words
'This fire is Vaishvanara' — one more meditation, taught the same way as before; this fire is Vaishvanara. But which fire is it? Here is the answer: the one living inside a person. Is it the fire that first shapes the body? No — it is the fire, called Vaishvanara, that digests whatever food you eat. And what is that food? Whatever is eaten, whatever creatures take in and enjoy — in plain terms, the fire in the belly. To point it out directly, this much is said: that digesting fire, the fire in the belly, makes a sound — and you can hear it if you cover your ears with your fingers. Meditate on that fire, Vaishvanara, as Prajāpati, and here too you come to share its very nature. And, in passing, here is a sign worth knowing: when the one who lives and experiences through this body is about to leave it, that sound goes silent — he no longer hears it.
Close to the Sanskrit
'This fire is Vaiśvānara' — another meditation, as before; this fire is Vaiśvānara. Who is this fire? He says: which is this one within a person. Is it the fire that begins the body? No, it is said: by which fire called Vaiśvānara this food is digested. What is that food? That which is eaten, enjoyed by creatures — the meaning is the gastric fire. For the sake of directly pointing it out, this is said: of that fire digesting the food, of the gastric fire, this is the sound that occurs. What is that? The sound — this 'this' being an adverbial qualifier — which one hears having covered the two ears, having made the covering with the fingers. One should meditate upon that fire, Vaiśvānara, as Prajāpati. Here too the fruit is assimilation to that nature. In this connection, an incidental sign of impending death is stated: this experiencer, here in the body, when about to depart, does not hear this sound.