Bhagavad Gita Chapter 2, Verse 26

अथ चैनं नित्यजातं नित्यं वा मन्यसे मृतम् | तथापि त्वं महाबाहो नैवं शोचितुमर्हसि ||

atha cainaṁ nitya-jātaṁ nityaṁ vā manyase mṛtam tathāpi tvaṁ mahā-bāho naivaṁ śocitum arhasi

But even if you think this is constantly born and constantly dies, even then, O mighty-armed, you should not grieve thus.

After 13 verses establishing the soul's eternity, Krishna makes a stunning pivot: 'Fine, even if you reject that—even if you think things are constantly being born and dying—you STILL shouldn't grieve.' If everything's perpetually cycling like waves on a shore, then this wave crashing is just the ocean being the ocean. Calling Arjuna 'mahā-bāho' (mighty-armed), Krishna essentially says: 'You're a warrior—you understand natural cycles. Why treat death like a catastrophe?' This is brilliant: grief doesn't fit either worldview—whether eternal souls or constant flux.