Can you describe how Sai Baba gave Udi and what it symbolized?

Sai Baba distributed Udi, which is sacred ash from his constantly burning Dhuni, as a form of benediction or Prasad. As detailed in Chapter 33, whether a person was small or great, Baba would give them Udi when they came for his Darshan and were about to leave. He would take handfuls of the ash, call it Prasad, and often apply it with his own thumb to the devotee's forehead. He would then place his entire hand on their head, wishing for their welfare. The terms ash, Vibhuti, and Udi all refer to this same sacred offering, which Baba distributed daily and without limit. This act symbolized a blessing and also carried a profound teaching about the impermanence of the physical world, as the chapter mentions this worldly life is like Udi.