Sri Aurobindo translates Chhandogya Upanishad, Chapter One, Section Two, Verses 10-14: “Angiras worshipped OM as breath in the mouth and men think of Breath in the mouth as Angiras because it is essence of the members of the body. By the strength of Angiras, Brihaspati worshipped OM as Breath in the mouth, and men think of the Breath as Brihaspati, because Speech is the great goddess and Breath is the lord of Speech. By the strength of Brihaspati, Ayasya worshipped OM as Breath in the mouth and men think of the Breath as Ayasya, because ’tis from the mouth it cometh. By the strength of Ayasya, Baka the son of Dalbha knew the Breath. And he became the Chanter of the Sama among the Naimishiyas and he chanteth their desires for them unto fulfilment. Verily he becometh a chanter unto fulfilment of the desires of men who with this knowledge worshippeth OM of Udgitha, the eternal syllable. Thus far concerning Self is the exposition.”
Shankara notes that Angirasa comes from the words “anga” and “rasa”, meaning the essence of the organs, or the Prana, which is the manifesting force of the Eternal, and one with the Eternal. This provides the key to understanding the symbolism here. Similarly, Brihaspati, the Lord of Speech, would also be a name that symbolizes the Prana.
If we go to the underlying sense of Brihaspati, In the Rig Veda, “Brihat” means great, or vast, as Sri Aurobindo has translated it. “Pati” means lord. So Brihaspati also is the Lord of the Vastness or Greatness, which again equates with the Eternal.
Speech proceeds from the Prana. The name Ayasya comes from a root that means inexhaustible, and is also an epithet for Prana. Once again, it comes back to the sense of worshipping OM as the Eternal, Prana as the Eternal, and in so doing, achieving all the results sought for in life and action in the manifested world. It is important to note the last sentence provides a key in advising us that this discussion relates to the “Self”.
Sri Aurobindo, The Upanishads, Chhandogya Upanishad, pp.349-366