For instance the Prophet Mohammed taught his disciples that the greatest debt every man had to pay was to his mother, and if he wished his sins to be forgiven he must so act through life that at the end his mother before passing from this earth would say, "I have forgiven you the debt." There was nothing a man could give or do, neither money nor service, which would enable him to say, "I have paid my debt"; no, his mother must say, "I have forgiven you that debt."