Can you explain the philosophical meaning of Udi as described in Chapter 33 of the Shri Sai Satcharita?

Chapter 33 elaborates on the profound spiritual significance of the Udi that Sai Baba gave to his devotees. The sacred ash is presented as a powerful symbol teaching that the entire visible universe is transient and ultimately as ephemeral as ash. The chapter conveys Baba's teaching that the human body, described as being made of five elements, is temporary and will eventually become ash once its destined experiences are over. By giving the Vibhuti, Baba intended to constantly remind both himself and his followers of this impermanence and to encourage the understanding that Brahman alone is the ultimate reality, while the cosmos is pervaded by Maya, or illusion.