How does Chapter 18 describe the supreme nature of the Sadguru?

Chapter 18 opens with a powerful invocation, hailing the Sadguru as the supreme Eternal one and the very Truth of Brahman. It describes Him as the Ruler of Maya, who, through direct experience, reveals the illusory nature of the world. The text celebrates the Sadguru as being without beginning or end, beyond duality, and without blemish. As detailed in this chapter, He is the ultimate teacher of the knowledge of the Self, capable of pointing out the Unperceivable One that even the Vedas and Shrutis debate endlessly, making this profound truth accessible to His devotees.