How did Sai Baba know the inner thoughts of his devotees? Can you provide an example from the scriptures?

Chapter 18 provides a powerful example of Sai Baba's omniscience. While the narrator was massaging Baba's feet, he silently felt a pang of envy, wondering why another devotee, Sathe, received grace after only a seven-day reading while his own years of devotion seemed unrewarded. As Chapter 18 recounts, Baba, the 'Crown of Saints,' immediately perceived this inner thought. This incident shows that Baba has his eye on all the good and bad desires that arise within us, and as the text states, 'Even if no one else knows it, Maharaj identifies it immediately.'