I’ll give a synopsis of all the chapters in the final section of Gita… The final 6 chapters share a common theme: how knowledge supports devotion. The idea is that true knowledge causes one to understand ones relationship to the divine and therefore fall all the more deeply in love with the divine. These 6 chapters expand upon a single text from the 12th chapter – 12.12 (“Shreyo hi jnanam abhyasat) – which says, “If you can’t take to devotion directly, cultivate knowledge – and this will help you fall in love with the divine.”
After hearing this, naturally one wants to know more about “knowledge” which can bring one to the blissful platform of divine love. Thus Arjuna asks questions that inaugurate the 6-chapter long section on such knowledge.
Chapter 13 introduces the subject. Knowledge consists of (1) the object to be known, (2) the subject gaining knowledge, and (3) the process of gaining knowledge. Spirit and matter and cultivation of knowledge-enabling character traits fill these roles.
“Spirit enters matter and becomes intertwined in it due to the desire to enjoy it’s transformations. Matter becomes attractive and addictive due to the power of “guna” – the three modes – which facilitate all transformations and variety in the world.” That’s 13.22, the seed of Chapter 14.
Chapter 14 is dedicated to explaining what the “three modes” are, giving several key examples of how they operate.
Chapter 15 more fully explains the conclusion of Chapter 14 – which is that there is a supreme reality, a supreme person – the object of devotion – which is beyond the three modes. So Chapter 15 introduces the spiritual world and the nature of that which is transcendental to matter and it’s transformations.
This chapter states that spirit can transmigrate upwards towards transcendence or downwards, deeper into bondage to matter.
Chapter 16 elaborates on the upward and downward transmigration of the spirit through the three modes of matter. It particularly focuses on character traits and personality types which typify a downward spiral, a de-evolution deeper into the modes of material nature, tightening the souls numbing immersion into matter.
Chapter 17 turns the discussion towards characteristics and traits of things which facilitate upward evolution through the three modes towards transcendence.
Chapter 18 closes the entire book. So this chapter summarizes and clarifies the entire message of the Gita – in a cohesive, evolutionary order.