Amidst both the armies (senayor ubhayor madhye), Krishna (hṛṣīkeśaḥ) speaks (uvāca) these (idaṁ) words (vacaḥ) almost laughingly (prahasann iva) to the grief-stricken (viṣīdantam) Arjuna (tam). (BG 2.10) This marks the beginning of the core instructions of the Bhagavad Gita.

Krishna begins speaking the Gita by chastising Arjuna, “You lament over (anvaśocas) what is not worthy of lamentation (aśocyān tvaṁ) and yet (ca) speak (bhāṣase) learned words (prajñā-vādāṁś). Those who are wise (paṇḍitāḥ) do not lament (nānuśocanti) either for the dead (gatāsūn) or for the living (agatāsūṁś ca).” (BG 2.11)

Why should we not lament? Indeed (eva), never was (na tv) there a time (jātu) when Krishna (ahaṁ) did not exist (nāsaṁ), nor Arjuna (na tvaṁ), nor all these (neme) kings (janādhipāḥ); and certainly (caiva) never (na) in the future (ataḥ param) shall any of us (sarve vayam) not (na) exist (bhaviṣyāmaḥ). (BG 2.12)

This drives home the point that our individuality cannot ever be taken away – either in our conditioned state or in our liberated state. A conscious living entity is an individual being now, had existed as an individual being in the past and will continue to remain an individual being in the future. In fact, that is also true for Krishna, maintaining his individuality as God eternally. A question arises at this point: What is it that maintains individuality for us? What is the distinguishing factor between the living and the dead? It is the presence of an individual soul within each body, as now clarified by Krishna.

As (yathā) the embodied soul (dehino) experiences childhood (kaumāraṁ), youth (yauvanaṁ) and old age (jarā) in this (asmin) body (dehe), it similarly (tathā) acquires (prāptir) a new body at death (dehāntara). A sober person (dhīras) is not bewildered (na muhyati) by this (tatra). (BG 2.13) This connects back to the message of BG 2.11 that the object of lamentation should never be the changing body.