I heard a story about Sai Baba and some grapes. Can you explain what happened with Boss Dharamsee and why it was a miracle?

The story you're referring to involves a man named Boss Dharamsee who was visiting Shirdi out of curiosity. As detailed in Chapter 35, Sai Baba began distributing grapes, which Dharamsee disliked because they had seeds and were unwashed. He internally questioned why a true saint would give him something he disliked. In response to this unspoken doubt, Baba urged him to eat more. When Dharamsee finally complied, he was astonished to find that the grapes in his mouth were completely seedless. This event was considered a miracle because Baba not only knew his innermost thoughts and dislikes but also altered the nature of the grapes specifically for him, transforming his skepticism into profound love and amazement at the saint's power.