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

Because of scripture, and because it is impossible, it must be a mere figure of
speech.
Purport by Śrīla Baladeva Vidyābhūṣaṇa
It is not possible that ether was created. This is confirmed by Kaṇāda Muni and
other great philosophers. The Taittirīya Upaniṣad's description of the creation of
ether is a mere figure of speech, as when, in ordinary speech one says, "Please
make some space" or "Some space has been made". For what other reasons is it
not possible that ether is created? Because it is impossible to create ether. It is not
possible to create ether because ether is formless and all-pervading, because it is
not included in the chain of causes, and because scripture proclaims that ether is
not created. Bṛhad-āraṇyaka Upaniṣad (2.3.2-3) proclaims:
vāyus cāntarīkṣaṁ caitad amṛtam
"Air and ether are both eternal."
This proves that ether was never created.
However, if the passage from the Taittirīya Upaniṣad used the word
"sambhūta" (created) only once to refer to the list of elements beginning with fire,
how is it possible to claim that this word is used literally for all the elements and
figuratively for ether alone?
The opponent of Vedānta replies in the next sūtra.
Sūtra 4
syāc caikasya brahma-śabda-vat
syāt—may be; ca—and; ekasya—of one; brahma—Brahma; śabda—the word;
vat—like.
It may be for one, as in the word "Brahman".
Purport by Śrīla Baladeva Vidyābhūṣaṇa
In the Taittirīya Upaniṣad (3.2) it is said: