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

"This is so because the root cause of everything is not caused by another root
cause."
In this way the doubt that perhaps the Supreme Personality of Godhead is
created by someone else is clearly refuted. Because the Supreme Personality of
Godhead is the first cause of all causes, by definition He is not caused by someone
else. However, the secondary causes, such as the avyakta and the mahat-tattva are
all created by another cause. The sūtras explaining that ether and the other
material elements were all created were given as examples of this general truth.
Adhikaraṇa 4
Fire Is Manifested From Air
Introduction by Śrīla Baladeva Vidyābhūṣaṇa
After concluding this discussion, we will consider what seems to be a
contradiction in the Śruti-śāstra's description of fire. Chāndogya Upaniṣad (6.2.3)
explains:
tat tejo 'sṛjata
"Then the Supreme Personality of Godhead created fire."
In this way it is explained that the Supreme Personality of Godhead created fire.
However, the Taittirīya Upaniṣad (2.1.3) explains:
vāyor agniḥ
"From air, fire is manifested."
These words explain that air created fire. Someone may say that in this second
quote the word "vāyoḥ" is in the ablative case (meaning "after air"), and in this
way there is no contradiction because both elements were created by the Supreme
Personality of Godhead, and fire was created after air was created.
Considering that someone may say this, the author of the sūtras speaks the