How did Sai Baba demonstrate that a devotee's faith could manifest a vision of Vitthal?

Sai Baba taught that Vitthal would appear if a devotee possessed sincere faith. As detailed in Chapter 4, He demonstrated this principle on multiple occasions. When Das Ganu was tasked with organizing a Name-week (Saptah), Baba placed a hand on His chest and firmly promised, "Yes, yes, the form of Vitthal will appear! But the devotee must be full of faith." Indeed, it is said that Das Ganu was granted a sight of Vitthal in Shirdi. Similarly, Kakasaheb Dixit received a vision of Vitthal during his morning meditation. This vision was validated when he visited Baba, who asked if "Vitthal Patil" had come, and was further confirmed when a seller arrived with pictures of Vitthal that exactly matched what Dixit had seen.