Acharya Prashant explains that the fundamental difference between love and lust lies in the direction of the mind rather than the physical act itself. While lust is a physical and mental activity driven by ego and self-projection, love is a state where the mind is oriented toward the ultimate truth or the divine. He clarifies that even a sage's physical interactions are distinct because their heart remains dedicated to the truth, whereas a worldly person's actions are rooted in hunger and violence. The quality of any relationship or physical union is determined by this internal orientation; love seeks to dissolve the self, while lust seeks to expand the ego.