Kṛṣṇa describes the staggering scale of cosmic time. He says that one day of Brahmā (the creator of the universe) lasts for a thousand cycles of the four ‘yugas’. His night is of the same immense duration. By human calculation, this is billions of years. Those who understand this vast timeline are called ‘aho-rātra-vidaḥ’, those who know the nature of day and night. This scale is intended to shrink our human ego. We worry about our 80-year lives as if they were eternity, but in the eyes of cosmic time, even the lifespan of a universe is just a passing moment. By revealing this, Kṛṣṇa helps Arjuna realize that material success and failure are tiny and fleeting. If even the life of Brahmā is just a day in the grand scheme, why get so attached to our small struggles? The wise person looks beyond these massive material cycles and seeks the Eternal Truth that remains unchanged even when billions of years have passed.