How does Chapter 18 describe the nature of a Sadguru and the experience of approaching one?

Chapter 18 opens by describing the Sadguru as the supreme Eternal one and the very Truth of Brahman. It uses a powerful analogy to explain the experience of approaching such a master. The text posits that if a salt doll enters the ocean to bathe, it can never return to its original form. As Chapter 18 explains, this is precisely what happens to a seeker who approaches the Sadguru; they merge with the divine and cannot return to their former state of separation, illustrating the complete and transformative dissolution of the individual self into the ultimate reality.