In the story of Boss Dharamsee, what is the significance of Tarkhad confirming his grapes had seeds?

The fact that Tarkhad's grapes still had seeds is a crucial detail that underscores the personal nature of the miracle for Boss Dharamsee. As Chapter 35 recounts, after Dharamsee experienced the seedless grapes, he asked Tarkhad about his. Tarkhad's confirmation that his grapes did have seeds proved that the miracle was not a general occurrence but a specific response to Dharamsee's internal state—his dislike and doubt. This eliminated any possibility that the entire bunch of grapes was coincidentally seedless and solidified for Dharamsee that Sai Baba had known his innermost thoughts and performed a miracle just for him, which left him "extremely surprised in his heart."