The teaching about the Atman, who or what we really are, that's the central teaching, entire Bhagavad Gita, is given in the second chapter. Arjuna asks questions and those questions you will see are not unnecessary, they are our questions. The 18th chapter is the last one because Arjuna has sort of, what's the term, cotton don to, to Sri Krishna's method of teaching. So the teaching is complete in 18 chapters but the essence of the teaching is given inthe second chapter.
Swami Sarvapriyananda teaches Chapter 2 (Verse 1-10) of the Bhagavad Gita. This series of talks unfolds the highest truths of Vedanta through the study of "The Song of God".