Purusottama, the whole person, is the topic of this chapter. Lord Krishna describes the tree of samsara, the nature of jiva (individual self), Ishvara, and finally purusottama, the substratum of all three. When we know this ultimate reality, we gain the fulfillment resulting from attaining all that is to be attained in life.
An Audio Course on Vedanta Texts- Bhagavad Gita: Bhagavad Gita (Chapter 15) by Swami Tattvavidananda Saraswati.
