According to the texts, how did Sai Baba use a simple offering of grapes to inspire faith in a devotee?

According to the narrative in Chapter 35, Sai Baba used a simple offering of grapes to engineer a profound transformation in Boss Dharamsee. Baba knew that Kaka had brought grapes with seeds, a variety Dharamsee disliked. He intentionally gave these grapes to Dharamsee, who was internally questioning Baba's abilities. The text states, 'As such an attitude arose in him, Baba gave him even more of them.' This act amplified Dharamsee's internal conflict. The resolution came when, at Baba's direct command, Dharamsee ate the fruit and was 'greatly surprised' to find them seedless. By turning the object of Dharamsee's dislike and doubt into a source of wonder, Baba proved his omniscience and shattered the devotee's ego, causing 'love for the saint' to be born in his heart.