गोविन्द भाष्य (श्रील बलदेव विद्याभूषण - अचिन्त्यभेदाभेद वेदान्त ब्रह्मसूत्र भाष्य सटीक)

sūtra explains: "Because that is the description". This means "Because it is
understood that the Supreme Personality of Godhead, as the all-pervading
Supersoul, moves the prāṇas and senses. In the Bṛhad-āraṇyaka Upaniṣad (3.7.16)
it is said:
yaḥ prāṇeṣu tiṣṭhan
"The Supersoul stays in the midst of the prāṇas and moves them."
That the demigods and the individual spirit soul may also move the prāṇas is
not disputed here, but the prāṇas cannot move themselves, for they are only inert
matter.
Hoping to enjoy, the individual spirit soul also moves the prāṇas. That is
described in the next sūtra.
Sūtra 15
prāṇavatā śabdāt
prāṇavatā—by the person who possesses the prāṇas; śabdāt—because of the
Śruti-śāstra.
By the person who possesses the prāṇas, because of the Śruti-śāstra.
Purport by Śrīla Baladeva Vidyābhūṣaṇa
The word "prāṇavatā" (the person who possesses the prāṇas) refers here to the
individual spirit soul. Hoping to enjoy, the spirit soul moves the prāṇas and
senses. Why is that? The sūtra explains: "śabdāt" (because of the Śruti-śāstra). In
the Bṛhad-āraṇyaka Upaniṣad (2.1.18) it is said:
sa yathā mahā-rājo jānapadān gṛhītvā sve janapade yathā-kāmaṁ parivartate evam
evaiṣa etat prāṇān gṛhītvā sve śarīre yathā-kāmaṁ parivartate.
"As a great king rules the subjects in his kingdom, so the individual spirit soul
rules the prāṇas in his body."