How did Sai Baba reveal to Cholkar that he knew about his secret vow regarding sugar?

Sai Baba revealed his omniscience to Cholkar in a subtle yet profound manner. After Cholkar arrived in Shirdi, had darshan, and distributed sugar to fulfill his vow, he went to stay with Jog. As recounted in Chapter 15, Baba then specifically instructed Jog, 'Give him cups of tea, well-filled with sugar.' This command stunned Cholkar, bringing tears of joy to his eyes. The significance lay in the fact that Baba himself did not drink tea, making his sudden concern for Cholkar's sugary tea a clear and direct sign. It was Baba's way of confirming that he was aware of Cholkar's secret vow, the long delay, and the personal penance of renouncing sugar, thereby validating Cholkar's deep faith.