What does Chapter 19 say is the main duty of human birth and the path to achieving it?

According to the teachings in Chapter 19, the ultimate fulfillment and primary duty of human birth is the attainment of the Supreme Self, which brings eternity, fearlessness, liberation, and independence. The chapter outlines a clear path to this goal, stating that there can be no liberation without knowledge. Furthermore, this essential knowledge cannot be attained without detachment from worldly things. The text emphasizes that the spark of detachment only arises when the mind truly perceives and understands that the world is transient. Therefore, as this chapter explains, recognizing the impermanent nature of existence is the crucial first step on the path to gaining the knowledge required for liberation.