Based on Chapter 18, what are some of the supreme qualities attributed to the Sadguru?

According to Chapter 18, the Sadguru is extolled with the highest reverence and attributed with supreme qualities. The chapter opens with salutations hailing the Sadguru as the "supreme Eternal one," the "Truth of Brahman," and the "Ruler of Maya." He is described as being beyond duality, without blemish, and both beginningless and endless. Furthermore, Chapter 18 emphasizes that the Sadguru is the ultimate teacher of the knowledge of the Self, who can effortlessly point out the "Unperceivable One" that even the Vedas and Shrutis debate endlessly. This chapter establishes the Guru's divine and transcendent nature.