What was the reason for Dev's confusion and inability to recognize Sai Baba as the Sanyasi at his feast?

Dev's confusion stemmed from a previous encounter with the Sanyasi. As explained in Chapter 40, before Dev had even invited Sai Baba to the Udyapan, the same Sanyasi had visited him to collect funds for cow protection. Because this first visit had a different, worldly purpose, when the Sanyasi returned on the day of the feast asking for a meal, Dev simply thought it was the same person coming back. He admitted later, 'how could I not guess that the Sanyasi was Baba? Because before the invitation was given to Baba, that first arrival had happened.' This prior context created a 'delusion' that prevented him from connecting the Sanyasi's presence with Baba's promise.