Can you explain the miracle involving Sapatnekar and the Dhangar woman? How did Baba reveal his omniscience?

The miracle occurred after Sapatnekar, in deep distress, resolved to hold Baba's feet. As he was massaging them, a Dhangar (shepherd) woman arrived and Baba began a conversation with her. Chapter 48 describes the miracle that followed: as Sapatnekar listened, he realized every word of the conversation was his own life story. Though the story was framed as being about a merchant, it contained intimate details of Sapatnekar's life, including the death of his late son. The Dhangar woman had no connection to these events; Baba was narrating the story to her, but it was meant for Sapatnekar. Hearing his life story from Sai's mouth filled Sapatnekar with wonder and deep respect, revealing Baba's profound inner knowledge.