According to Chapter 50, why is Sai Baba's greatness considered indescribable, and how is he compared to the sun and moon?

Chapter 50 conveys that the greatness of Sai Baba, the "King of Gurus," is truly "unfathomable," to the point where "the pride of speech dissolves" when trying to describe it. The author suggests it is better to be humble and silent. The chapter attempts a comparison to celestial bodies only to show its inadequacy. As Chapter 50 explains, it is not fitting to compare Sai to the sun, because the sun eventually sets. Likewise, a comparison to the moon is also insufficient, as the moon wanes. In stark contrast, the text proclaims, "Sai is forever complete." This comparison serves to highlight Sai's eternal, unchanging, and perfect nature, which transcends the limitations of even the most powerful elements of the physical world.