In "The Alchemist," how was Santiago led back to the treasure he was looking for?

Santiago began his treasure hunt after dreaming that he would find one if he went to the Great Pyramids.  It took several years for him to get there, but he did make it to Egypt.  When digging a hole thinking that his tresaure was buried in the sand, Santiago was attacked by renegades from the desert.  When the gang finally left him bleeding on the ground, the leader of the renegades told the boy that he, too, had once had a dream that he'd found a great treasure buried under a tree in a deserted church in Spain, but he wasn't stupid enough to go across a desert because of a dream.  Santiago recognized the place the renegade described because it is the precise spot where he'd had his dream about the Pyramids.  Santiago returned to Spain and found his treasure at last.