What are the main teachings and stories concerning Udi in Chapter 33 of the Shri Sai Satcharita?

Chapter 33 of the Shri Sai Satcharita is dedicated to explaining the glory of Udi, or sacred ash. It describes Sai Baba's daily practice of maintaining a sacred fire (Dhuni), into which he would offer firewood, and then distribute the resulting ash to devotees. The core teaching, as detailed in this chapter, is that the Udi symbolizes the impermanence of the material world. Baba used it to teach that the visible universe is transient, like ash, and that our own bodies, made of five elements, will eventually turn to ash once their destined experiences are over. It served as a constant reminder that only Brahman is real and the universe is an illusion (Maya).