In this chapter, Krishna dwells further on the declaration in the previous chapter that one should achieve renunciation of Karma not by absolving from them, but through unattached action (nishkama karma) rooted on the true knowledge.
He is talking about the Yoga Vidya, referring to it as the ultimate and most concealed knowledge out there:
The wisdom I imparted to the Sun was passed down to Manu and Ikshwaku, and from them to the Rajarshis. Yet, over time, this sacred knowledge was lost somewhere. Now, I am passing it on to you, as my dear and devoted friend. 
To a natural doubt from Arjuna at this point, regarding Krishna’s birth that happened so many yugas post the birth of Sun, Krishna responds this way: I have taken many births, as have you. I (who have mastered this divine yoga) remember them all—but you (who have yet to attain that mastery) do not.
I, the Ishwara, the consciousness that resides within all beings, have taken form as various lives across the ages. In each yuga, whenever dharma declines and adharma rises, I manifest to restore balance.
Countless purified practitioners have realized this truth about me, freeing themselves from desires, fear, and anger, and have thereby reached that state of mine themselves.
Though people worship me in different ways, all paths ultimately lead to me. Some seek material gains and worship various gods and goddesses, but I am the force behind the four-fold divisions of humanity, based on their guna and karma. Yet, it must be understood that I am not the ‘doer’ of these actions; I remain detached from them all.
– (Chapter 4; Verses 1-15)
Krishna goes forward to explain the difference between Karma and Akarma that even great scholars struggles to understand correctly:
One who sees Akarma in Karma (inaction within action) and Karma in Akarma (action within inaction) is the true Jnani, Yogi, and wise scholar. Such a person, free from attachment to the outcomes of their actions and ever content, remains untouched by the consequences—whether virtuous or sinful—of their Karma. These actions, performed as an offering in the spirit of Yajna, become one with Prakriti itself.
The Yajna fire, the offering poured into it, the tools used for the ritual, the one performing the act, and the act of pouring itself—all are Brahman, the ultimate reality. People may perform these Yajnas from different perspectives, but Krishna explains that the various types of Yajnas mentioned in the Vedas all stem from Karma. However, a Yajna performed with true knowledge (jnana) surpasses all materialistic offerings. Ultimately, all actions are paths leading toward that higher knowledge.
That knowledge must be sought from a self-realized Guru, with utmost devotion, service, and continuous inquiry to clear all doubts. One who attains this knowledge is never deluded, for they see all beings as part of the self and the self within Ishwara. This wisdom is so powerful that it burns away all sins and karmic bondages, reducing them to ash.
A self-realized Jnani, who has renounced attachment to actions through yoga, is no longer bound by karma. Therefore, cut through the doubts born of ignorance with the sword of knowledge, and rise!
– (Chapter 4; Verses 1-15)
Throughout the Gita, Krishna’s use of “I,” “me,” and “my” must be understood in context. For instance, at the beginning of this chapter, when he says, “the wisdom I imparted to the Sun,” he speaks from the level of Parameshwara, rooted in the realization of Aham Brahmasmi (I am Brahman). However, when he says, “I have taken many births, as have you. I remember them all—but you do not,” he speaks from the individual perspective, as Krishna the yogi, acknowledging the difference in spiritual awareness between himself and Arjuna.
In this chapter, there’s a statement that aligns with the Hindu concept of Avataara, but it makes clear that it’s not limited to ten or any specific number of divine incarnations. Rather, it also emphasizes that many beings have reached the level of Yogeswara through the realization of truth. The idea that some are born as Yogeswaras while others rise to that level during their lifetime sends a powerful message: every birth carries the potential for such spiritual elevation! It underscores that anyone can attain this state through devotion, self-realization, and inner growth.
It is also explained that although Ishwara is the fundamental cause behind everything in the universe, individual actions (karma) occur at the level of each being, driven by their Guna and Vasana (inherent and acquired tendencies). Therefore, Ishwara is not the doer of these actions. One who has reached the state of the “eternal witness” through yoga perceives inaction (akarma) within every action (karma). This means that even while performing one’s duties with utmost skill, there is no sense of personal doership—no attachment to “I am the doer.” All actions are recognized as stemming from the Guna and Vasana of the body and mind and are seen as part of the natural order (Prakriti) and an offering (Yajna). It is through this realization that one renounces one’s karma (true meaning of karma sannyasa) and becomes free from the bonds of karma. This is the essence of the chapter.
