What is the deeper meaning behind the Udi and its power, as explained in these passages?

Chapter 33 explains that the Udi is "supremely auspicious" and that Sai Baba, as the "helmsman of the path of spiritual welfare," gives it to fulfill both worldly interests and promote spiritual well-being. The text highlights that the stories of its benefits are countless. However, the story of Narayanrao's friend and the incense ash reveals a deeper truth about its power. The narrative explicitly states that although it was only ash from incense sticks, "being considered as Udi from the path, such was the experience manifested." This implies that the physical substance is a medium, but the true power is activated by the devotee's faith and their consideration of the substance as sacred Prasad from Sai.