Chapter 49 mentions that speech is inadequate to describe the Sadguru. Can you explain the different types of speech referenced and why they fail?

Chapter 49 explains the Sadguru's inexpressible nature by referencing a hierarchy of speech. It mentions that 'Para,' or transcendental speech, returns, unable to describe Him. Following this, the chapter notes that 'Pashyanti' and 'Madhyama,' which are the middle and subtler stages of speech before vocalization, also fail to 'open their mouths.' The author then logically concludes that if these higher forms of speech are powerless, the fourth and most external form, 'Vaikhari' (the spoken word), has no chance of comprehending or articulating the Sadguru's inconceivable art. This illustrates the profound and unfathomable greatness of Sai as portrayed in this chapter.