How does the author use the concepts of different stages of speech (like Para and Vaikhari) to illustrate the challenge of describing Sai Baba?

In Chapter 49, the author expresses the inadequacy of language to capture Sai Baba's true nature. He explains that his own spoken words, or 'Vaikhari', are insufficient for the task. To emphasize this, he references higher, more subtle stages of speech, stating that even the 'Para' (transcendental) speech returns from where Sai's greatness begins, and that 'Pashyanti' and 'Madhyama' (middle stages) do not even "open their mouths." This illustrates that Sai's essence is beyond all forms of human expression and comprehension. The author concludes that only by surrendering at the Sadguru's feet, not through words, can one begin to grasp the true form.