Etena matarisva vyakhyatah II.3.8 (224)

By this i.e., the foregoing explanation about Akasa being a product, (the fact of) air (also being an effect) is explained.

Etena: by this, i.e., the foregoing explanation about Akasa being a production, by this parity of reasoning; Matarisva: the air, the mover in mother, space; Vyakhyatah: is explained.

This Sutra states that air also, like Akasa, has been created by and from Brahman.

The present Sutra extends the reasoning concerning Akasa to the air of which the Akasa is the abode. The Purvapakshin maintains that the air is not a product, because it is not mentioned in the chapter of the Chhandogya Upanishad which treats of the origination of things. The Purvapakshin says that the birth of air mentioned in the Taittiriya Upanishad is figurative only, because air is said to be one of the immortal along with Akasa.

"Vayu (the air) is the deity that never sets" (Bri. Up. I.5.22). The denial of Vayu's never setting refers to the lower knowledge or Apara Vidya in which Brahman is spoken of as to be meditated upon under the form of Vayu and is merely a relative one.

The glory of Vayu is referred to as an object of worship. The Sruti says "Vayu never sets." Some dull type of men may think that Vayu (air) is eternal. To remove this doubt there is made a formal extension of the former reasoning to air also.

Vayu is called deathless or immortal only in a figurative sense. Vayu (air) also has origin like Akasa.