How does Chapter 52 describe the ultimate union between a devotee and the Guru, particularly concerning the concept of duality?

Chapter 52 uses powerful metaphors to explain the dissolution of duality in the union between a devotee and the Guru. It states that when a devotee takes refuge, the Guru ensures no sense of duality remains, just as a river forgets its 'river-ness' upon embracing the ocean. Another analogy provided in the chapter is that of two lamps becoming one when they embrace; the state of duality immediately vanishes, leaving only a single, unified light. Through this power of love, Sai made His faithful devotees liberated while still in the body.