In the fourth chapter of the Gita there comes an important verse that is frequently recited before taking food, as a reminder. It runs “Brahman is the giving, Brahman is the food-offering, by Brahman it is offered into the Brahman fire, Brahman is that which is to be attained by Samadhi in Brahman-action.” (Gita IV. 24)
The synthesis undertaken by the Gita involves the expansion of terms such as “sacrifice” and “works” from their egoistic limited sense that starts from the human perspective, to the ultimate metaphysical sense implied in the entire creation being an expression and manifestation of the one universal Being, which the Gita names the Purusottama (literally “supreme Purusha”) which encompasses both the immutable and immobile Akshara Purusha, as well as the mutable Purusha, Kshara Purusha interacting with Nature, Prakriti.
Sri Aurobindo explains: “The Brahman is one but self-displayed in two aspects, the immutable Being and the creator and originator of works in the mutable becoming….it is the immobile omnipresent Soul of things and it is the spiritual principle of the mobile working of things, Purusha poised in himself and Purusha active in Prakriti; it is akshara and kshara. In both of these aspects the Divine Being, Purushottama, manifests himself in the universe; the immutable above all qualities is His poise of peace, self-possession, equality….; for that proceeds His manifestation in the qualities of Prakriti and their universal workings; from the Purusha in Prakriti, from this Brahman with qualities, proceed all the works of the universal energy, Karma, in man and in all existences; from that work proceeds the principle of sacrifice.”
The link to the concept of sacrifice in its widest sense comes about through the understanding that all energy is created by and for, and enjoyed and received by the divine Being. “For all the working of Prakriti is in its true nature a sacrifice, yajna, with the Divine Being as the enjoyer of all energisms and works and sacrifice and the great Lord of all existences…., and to know this Divine all-pervading and established in sacrifice…is the true, the Vedic knowledge.”
Sri Aurobindo, Essays on the Gita, First Series, Chapter 12, The Significance of Sacrifice, pp. 108-110