How did Sai Baba use a simple cup of tea to demonstrate his omniscience to his devotee, Cholkar?

The story of Cholkar highlights Sai Baba's omniscience through a seemingly simple act involving tea. As recounted in Chapter 15, Cholkar had secretly taken a vow to abstain from sugar until he could visit Shirdi, a trip delayed by financial hardship. When he finally arrived and fulfilled his vow, he was a guest at Jog's place. At that moment, Sai Baba, who did not drink tea himself, specifically instructed Jog to serve Cholkar "cups of tea, well-filled with sugar." This instruction astonished Cholkar, bringing tears to his eyes, because it proved that Baba was intimately aware of his secret, personal vow and the long penance he had undertaken, thereby confirming his faith in a profound way.