Krishna furthermore delineates the nature of the soul. One who (ya) thinks (vetti) the soul (enaṁ) a killer (hantāraṁ) and (ca) one (yaś) who thinks (manyate) it (enaṁ) killed (hatam) – they (tau) both (ubhau) are not (na) in knowledge (vijānīto) – the soul (ayaṁ) neither (na) kills (hanti) nor (na) is killed (hanyate). (BG 2.19) Is this fact true forever? The next verse emphatically confirms it to be true forever.
The soul (ayaṁ) neither (na) takes birth (jāyate) nor (vā) dies (mriyate) at any time (kadācin) – it had not (na) come into existence (bhūtvā), nor (vā na) will it ever come into existence (bhūyaḥ) in the future (bhavitā). The soul (ayaṁ) is unborn (ajo), eternal (nityaḥ), ever-existing (śāśvato) and primeval (purāṇo). It is not killed (na hanyate) when the body is killed (hanyamāne śarīre). (BG 2.20) How (kathaṁ) can a person (sa puruṣaḥ) who (ya) knows (vedā) the soul (enam) to be indestructible (avināśinaṁ), eternal (nityaṁ), unborn (ajam) and inexhaustible (avyayam) kill (hanti) anyone (kaṁ) and whom (kaṁ) can one cause to kill (ghātayati)? (BG 2.21)
In that case, what happens at death? Krishna gives an analogy to help us understand the point of death. As (yathā) a person (naro), giving up (vihāya) old garments (vāsāṁsi) that are worn out (jīrṇāni), puts on (gṛhṇāti) new (navāni) ones (aparāṇi), similarly (tathā), the embodied soul (dehī), giving up (vihāya) worn-out (jīrṇāny) bodies (śarīrāṇi), accepts (saṁyāti) new (navāni) ones (anyāni). (BG 2.22) This connects back to BG 2.13, where Krishna pointed out how a sober person is not bewildered by the change of body at the time of death.