Based on the text, what is the true nature of the Soul, and what analogies are used to explain its untainted quality?

Chapter 19 delves into the profound nature of the Soul, describing it as distinct from the body, senses, mind, and life-force. It is self-luminous, pure consciousness, changeless, and formless. To illustrate how the Soul remains untainted by the world, the chapter uses the powerful analogy of a crystal. Just as a crystal appears to take on the color of objects near it—be it red, black, or yellow—it remains intrinsically pure, colorless, and distinct from those colors. Similarly, the Soul may appear to be affected by the actions of Maya and the world, but it remains fundamentally untainted and unchanged. The chapter also compares the false perception of the self to seeing a snake in a coiled rope, emphasizing that the ego of 'I am the body' is a false bondage.