Yajna, sacrifice, is a state of inaction in action. Here the actor or doer is observing from a distance the actions of the mind/body complex and one does not feel as though one is doing the action. Thus, one feels that the body is acting out of a natural impulse, prarabdha karma, that was set in motion in previous births, including the present birth. The gunas, which make up the body, are thus interacting with the gunas as objects in the objective or outer world.
Language on how this process unfolds is necessarily limited due to the fact that the experience of being a non-doer is beyond the mind's conceptual realm.