How does Chapter 18 describe the transformative impact of a Guru's grace on a devotee?

Chapter 18 uses a powerful metaphor to explain the effect of a Guru's grace. It poses the question of whether a salt doll that enters the ocean to bathe can ever return, concluding it's impossible. This is likened to a devotee who approaches the Guru; they merge and become one with the divine, losing their separate identity. As stated in this chapter, when one is fortunate enough to receive the Guru's grace, the divisive and false logic of "mine" and "thine" completely disappears, leading to a state of unity and self-realization.