What does Chapter 18 say about the effect of a Guru's grace on a person's perception of the world and others?

Chapter 18 reveals that receiving the Sadguru's grace fundamentally transforms a person's perception. The text explicitly states that if one is fortunate enough to fall within the Guru's grace, the false logic of "mine" and "thine"—the sense of separation between "us" and "them"—finds no place. This dissolution of duality is a key outcome. The chapter opens by praising the Guru for showing the world to be an illusion, implying that grace allows a devotee to see beyond the superficial reality to the underlying truth of Brahman. This shift in perception, as described in Chapter 18, moves a person from a state of division and ego to one of unity and spiritual clarity.