What does Chapter 25 teach about the concept of one-pointed devotion and its relationship to the Sadguru?

Chapter 25 highlights that Sai Baba, as the supreme embodiment of mercy, desires "one-pointed devotion" from his followers. The chapter explicitly states that a devotee who is faithful and filled with such devotion will lack nothing in attaining their desires. To clarify this concept, the text quotes Krishna's words to Uddhava: "The Sadguru is indeed My own form." This implies that one-pointed devotion is achieved by worshipping the Sadguru with love. As explained in Chapter 25, once this unwavering faith is established in a devotee, Sai Baba personally wards off all their misfortunes and removes their suffering, granting their desired objects.