Krishna begins the fourth chapter by describing the history of the knowledge he is sharing with Arjuna. At the dawn of creation, Krishna gave this imperishable knowledge to the sun-god Vivasvan, who gave it to the progenitor of humanity Manu, who in turn gave it to the illustrious king Ikshvaku (04.01). In this way, through a disciplic succession, this knowledge was made accessible to saintly kings, but with the eroding effects of mighty time, that access was lost (04.02). Krishna declares that he is now speaking that same ancient knowledge to Arjuna because Arjuna is both Krishna’s devotee and friend (04.03).

Arjuna interrupts Krishna to clarify a seeming anachronism: When Krishna was born later and Vivasvan was born earlier, how can Arjuna make sense of Krishna’s claim to have instructed Vivasvan? (04.04). Krishna answers by stating that they both have had many previous lives, but Krishna remembers all of them, whereas Arjuna has forgotten about them (04.05). Explaining the cause of this difference in their memories, Krishna asserts that he is not only unborn and imperishable like all living beings; he is also the Lord of all living beings — and he comes to this world by his own potency, not by the illusory energy, thereby retaining his divine omniscience (04.06). Whenever dharma (virtuous social order) declines and adharma increases, he chooses to appear by his own will (04.07). To protect the virtuous, to neutralize the vicious and to establish dharma, he appears in every cosmic cycle (04.08). By his descent, he makes himself accessible to others — those who truly understand the divine nature of his birth and activities become so attracted to him as to attain him in his eternal abode (04.09). Asserting that many have become thus liberated, Krishna emphasizes the purifying power of knowledge about him: it can free us from the binding forces of desire, fear and anger; and infuses us with attraction for him (04.10).