The Yoga of Knowledge
Chapter two is where the Gītā actually opens. It is the longest answer in the book and the one all the others come out of: what in you does not die, what work is for, and how a person can be steady while everything around him is not.
But none of it arrives straight away. The chapter begins with a sharp word, and then Arjuna, still sitting on the floor, does something that costs more than standing up would have. He names his own weakness out loud, and asks to be taught.
The word he uses for that weakness is कार्पण्य, the fault of a miser: the closed hand, the nature that will not give. It is the one door in this chapter we have opened so far, and it turned out to be about everybody in the room rather than about him.
Everything after it in this chapter is answer. The steadiness, the work without its fruits, the man who is awake in what is night for everybody else. And one passage, later on, that describes how a person is taken apart, step by step, more exactly than most things written since.