How does Sai Baba use others to convey his teachings, and what does this reveal about his nature?

Sai Baba's method of teaching is subtle and often involves using others as instruments for his divine will. For instance, as described in Chapter 19, a narrator had just resolved to focus his mind on the name of Rama when he heard a devotee, Aurangabadkar, singing a song about that very subject. The narrator realized this was no coincidence, concluding that we are all merely puppets and the puppeteer is Mother Sai. Baba pulls the strings, and inspiration happens accordingly, showing a direct proof of his ability to know one's inner thoughts and provide guidance without speaking himself, thus revealing his all-pervasive nature.