Kṛṣṇa describes the massive cycles of time. He says that at the end of a ‘kalpa’ (a day of Brahmā), all material manifestations dissolve back into His own nature. They go into a dormant, unmanifest state. Then, at the beginning of another ‘kalpa’, He creates them all again. The universe ‘breathes’—manifestation is the exhalation, and dissolution is the inhalation. This reinforces the idea that the world is Kṛṣṇa’s energy in motion. We are part of a grand cosmic rhythm that has been repeating for eternity. Our current identity is just one ‘wave’ in this ocean. By revealing this, Kṛṣṇa is de-escalating Arjuna’s anxiety about the war. He is showing that birth and death are part of a massive, automated system that He directs. The ‘end’ of the warriors on the battlefield is just a tiny part of the ‘kalpa-kṣaye’, the eventual dissolution of everything material. Understanding this scale takes the personal pressure off Arjuna’s shoulders.