None but angels have We appointed as wardens of the Hell-fire. We have fixed their number in order to purify (and purge) the sins of those who disbelieve. The result of this is that the people of the Scripture will be convinced, and those who believe will increase in faith (and act with righteousness). And those who have been given the Scriptures as well as the believers may (both) attain certainty (and will not be misguided). And the people with diseased hearts and the disbelievers will say, `What does Allâh mean by such an illustration?' Thus does Allâh forsake him who wishes (to go astray), and guides him who wishes (to be guided). And none knows (the number) of the hosts of your Lord but He. And this (Qur'ân) is nothing but a means for human beings to rise to eminence.