How did the shopkeepers react after they denied Baba oil and saw the lamps burn with water?

Their reaction was one of immediate shock and subsequent repentance. According to the account in Chapter 5, upon seeing the water-fueled lamps burn, the grocers 'put their fingers in their mouths,' a sign of utter amazement. They instantly realized their mistake, saying to themselves that they had wronged Baba by lying. As the lamps continued to burn throughout the night without a single drop of oil, their amazement turned to fear and remorse. The text states they 'began to tremble everywhere,' feeling deep repentance for having sinned and given Baba needless trouble, recognizing the immense power they had just witnessed.