Bhagwad Gita
Chapter 2, Verse 26
अथ चैनं नित्यजातं नित्यं वा मन्यसे मृतम्।
तथापि त्वं महाबाहो नैवं शोचितुमर्हसि।।2.26।।
If you believe that the soul is always being born and always dies, you still have no reason to grieve, O mighty-armed one.