According to Chapter 10, what is the role and significance of a Sadguru, and how can one benefit from their grace?

Chapter 10 powerfully articulates the supreme importance of the Sadguru. It states that while all other gods are illusory, the Guru alone is the one eternal God. By placing faith in the Guru's feet, one's destiny can be changed, as the Guru "strikes a nail over the lines of destiny." The text further explains that devoted service to the Sadguru can completely destroy worldly existence (Samsara) and help devotees cross the three types of miseries. As mentioned in Chapter 10, just as one trusts a boatman to cross an ocean, one must trust the Guru to cross the ocean of existence. In return for devotion and faith, the Sadguru bestows Knowledge and liberation effortlessly.