What does this chapter say about the power and importance of a Sadguru for a devotee?

Chapter 10 emphasizes that the Sadguru is paramount in a devotee's spiritual journey. The text states that while all other gods are illusory, the Guru is the "one eternal God." By placing faith in the Guru's feet, a devotee's fate can be changed, an act described as the Guru striking "a nail over the lines of destiny." The chapter further explains that the Sadguru acts as a boatman, guiding followers across the "ocean of existence" (Bhavasagar) and helping them overcome the three types of miseries. Through the Guru's grace, devotees can have their karmas destroyed and effortlessly attain liberation and bliss.