English Translation Of Sri Shankaracharya's Sanskrit Commentary By Swami Gambirananda
8.4 Adhibhutam, that which exists in the physical plane, i.e. that which exists by comprising all creatures;-what is it?-it consists of the ksarah bhavah, mutable entity. Ksarah is that which is mutable, which is destructible; bhavah means anything whatsoever that has orgination. This is meaning.
Purusah means the Person, derived in the sense of he by whom all things are pervaded; or, he who lies in every heart. He is Hiranyagarbha, who resides in the Sun and sustains the organs of all creatures. He is adhi-daivatam, the entity existing in the divine plane.
Deha-bhrtam-vara, O best among the embodied beings; adhiyajnah, the entity existing in sacrifices, is the Deity, called Visnu, presiding over all sacrifices-which agrees with the Vedic text, 'Sacrifice is indeed Vishu' (Tai, Sam. 1.7.4). Aham eva, I Myself, who am that very Visnu; am adhiyajnah, the entity existing in the sacrifice; which is going on atra dehe, in this body. Since a sacrfice is performed with body, therefore it is closely associated with the body. In this sense it is said to be going on in the body.