Verse 4.3.3

अथाध्यात्मं प्राणो वाव संवर्गः स यदा स्वपिति प्राणमेव वागप्येति प्राणं चक्षुः प्राणं श्रोत्रं प्राणं मनः प्राणो ह्येवैतान्सर्वान्संवृङ्क्त इति ॥ ४.३.३ ॥

athādhyātmaṃ prāṇo vāva saṃvargaḥ sa yadā svapiti prāṇameva vāgapyeti prāṇaṃ cakṣuḥ prāṇaṃ śrotraṃ prāṇaṃ manaḥ prāṇo hyevaitānsarvānsaṃvṛṅkta iti || 4.3.3 ||

3. Next is the worship concerning the body. Prāṇa swallows everything. When a person sleeps, speech, the eyes, the ears, and the mind—all these go into prana. Prāṇa swallows all these.

Word-for-word explanation:

Atha adhyātmam, now, that relating to the body; prāṇaḥ vāva samvargaḥ, prāṇa [the vital force] swallows everything; saḥ yadā svapiti, when a person is sleeping; prāṇam eva vāk apyeti, speech disappears into prāṇa; prāṇam cakṣuḥ, the eyes [disappear] into prāṇa; prāṇam śrotram, the ears [disappear] into prāṇa; prāṇam manaḥ, the mind [disappears] into prāṇa; prāṇaḥ hi eva etān sarvān saṃvṛṇkte iti, prāṇa swallows all these.

Commentary:

When a person falls asleep, the sense organs stop working. They retire into prāṇa, as if they have been swallowed by it.