And We have not appointed the guardians of hell, other than the angels, and We have not fixed their number but for the affliction of those who do not believe. So that those who are given the book may be certain and those who believe may increase in belief and those who were given the book and the believers may not be doubtful. And those in whose hearts is a disease and the infidels may say, “What does Allah intend by this similitude?” Thus Allah leaves to stray whom He wills and He guides whom He wills and no one knows the forces of your Fosterer except He Himself and this is nothing but a reminder to man. (R 1)