What is the ultimate purpose of human life, and how does understanding the Soul's true nature relate to it?

The ultimate purpose of human birth is not merely earning money, but earning the knowledge of Truth. Chapter 8 explains that this Truth is the knowledge of non-duality (abheda), also known as Brahma-vidya. The goal is to remove the 'oil' of worldly desires and the 'soot' of ignorance to let this knowledge shine. We are advised to use knowledge to remove ignorance, and then transcend both to remain in the pure state of our own nature. Chapter 8 stresses the importance of striving for this Self-knowledge before the body falls, as it is the key to achieving satisfaction in one's own nature and fulfilling the purpose of human birth.