Describe the different instances where Sai Baba's devotees received a vision of Lord Vitthal in Shirdi.

Chapter 4 recounts multiple instances where devotees experienced visions of Lord Vitthal. In one case, Sai Baba instructed Das Ganu to organize a week-long recitation of God's name (a Saptah), promising that Vitthal would appear if the devotee was full of faith. The text confirms that at the end of the week, Das Ganu was granted a sight of Vitthal in Shirdi. In another beautiful story, Kakasaheb Dixit had a vision of Vitthal during his private morning meditation. When he later went for Baba's darshan, Baba confirmed the experience by asking, "Vitthal Patil had come, right?" and humorously advised him to "Nail him down and make him steady." The proof was solidified when a traveling merchant arrived that afternoon selling pictures of Vitthal, one of which was an exact replica of the form Kakasaheb had seen in his vision.