The Immortality of the Self
Krishna's opening metaphysical argument — the self that inhabits the body is not the kind of thing that is born or dies.
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BG 2.20
He is not born, nor doth he die; nor having been, ceaseth he any more to be; unborn, perpetual, eternal and ancient, he is not slain when the body is slaughtered.
BG 2.22
As a man, casting off worn-out garments, taketh new ones, so the dweller in the body, casting off worn-out bodies, entereth into others that are new.
BG 2.23
Weapons cleave him not, nor fire burneth him, nor waters wet him, nor wind drieth him away.