In the first chapter of Geeta, Vyasa chariyar revealed the human problem of samsara in the form of raga (emotional depedents of external factors), sogaha (grief or sorrow) and moga (delusion or conflict or indiscriminate). When Arjuna had this problem in the battlefield, he tried to solve this problem himself and was not successful and took the action of surrendering to the Lord. Lord Krishna accepted the role of Guru
In the second chapter, Krishna took the approach that the self-knowledge is the only solution. No other solution can solve the problem. And therefore, Krishna tried to give the self-knowledge to Arjuna. Geeta talks about many topics but Gaeta’s primary teaching is atma vidhya. In this chapter, Krishna gives the entire range of sadhanas for this knowledge. In this chapter, Krishna taught the two sadhanas: Karma yoga and gyana yoga. Karma yoga is prescribed as a means of mental purity. Krishna makes it clear that karma yoga can only give preparatory knowledge. Gyana yoga involves self-inquiry through the scriptures under the guidance of a competent guru. The second chapter is the summary of Geeta.
The third chapter is elaboration of karma yoga. The fourth and fifth chapters are expansion of gyana yoga.
Krishna takes a small diversion initially to discuss two topics of chapter 4. The two topics are and glorification of Geeta and avatara ragasyam. Krishna wants to emphasize that the teachings of Geeta are vedic teachings and are beginning-less.
The Lord said I imparted this eternal yaga to Lord Sun. Lord Sun taught the same to Manu. Manu taught it to Iksvaku.
I have given the same teaching in the form of Veda. Krishna says Geeta is the new name for Veda. I revealed this wisdom to Surya Bagawan. This teaching can never go out of date. It is relevant even now in the 20th century.
Surya Bagawan taught this teaching to Manu. Manu taught this to the King Ikshvaku.
Oh Arjuna! The royal sages knew this which was thus traditionally handed down. Due to long passage of time that yaga is lost in this world.
All the raja rishis (kings) knew this teaching. Gradually people started losing interest in this teaching. Therefore, Krishna is revising this teaching in the form of Geeta.
That very same ancient yoga in this which has been taught by Me to you now, because you are My friend and devotee. This indeed is the highest secret.
Veda Purva teaches karma yoga and called karma kandam. Veda Anta teahes gyana yoga and is called gyana kandam. This is the oldest teachings. Krishna chose Arjuna for this teaching, because Arjuna asked for it and because Arjuna is the friend of Krishna.
Self-knowledge is the greatest secret, because what we are searching for is within ourselves. Therefore this wisdom is called uthama ragasiyam.
Arjuna asked: Your birth is later. The birth of Lord Sun is much earlier. How am I to understand this statement of Yours that You have taught Lord Sun in the beginning of the creation?
Vedas are called sruthi because the Rishis heard internally; all other scriptures are called smirhti.
Arjuna says that I can understand that you are teaching me Geeta, but I can’t understand how you can also teaching Surya Bagawan at the time of creation, when we both are of the same age. What is the secret of your contrary statement? If you have taught Surya Bagawan, you can’t teach me If you are teaching me, you can’t teach Surya Bagawan. As an answer to this question, Krishna will discuss Avataras.