Acharya Prashant explains the profound meaning of sacrifice as described in the Mundaka Upanishad and the Bhagavad Gita. He clarifies that true sacrifice is not merely the ritual of lighting a fire and offering oblations, which are only symbolic representations. Instead, real sacrifice is selfless action, where one performs their duties without any desire for personal gain or results. By dedicating all actions and their fruits to the highest goal, an individual's mind becomes divine and attains a state comparable to heaven. This process of selfless action is intended to lighten the burden of the ego and lead to liberation from one's limited identity.