And with Him are the keys of the secret things; none knoweth them but He; He knoweth whatever is on the land and in the sea; and no leaf falleth but He knoweth it; neither is there a grain in the darknesses of the earth, nor a thing green or sere, but it is noted in a distinct writing.
It is He who taketh your souls at night, and knoweth what ye have merited in the day: then he awaketh you therein, that the set life-term may be fulfilled: then unto Him shall ye return; and then shall he declare to you that which ye have wrought.
Supreme over his servants, He sendeth forth guardians who watch over you, until, when death overtaketh any one of you, our messengers take his soul and fail not:
Then are they returned to Allah their Lord, the True. Is not judgment His? Swiftest He, of those who take account!
Verily We have revealed the Book to thee in Truth, for (instructing) mankind. He, then, that receives guidance benefits his own soul: but he that strays injures his own soul. Nor art thou set over them to dispose of their affairs.
It is Allah that takes the souls (of men) at death; and those that die not (He takes) during their sleep: those on whom He has passed the decree of death, He keeps back (from returning to life), but the rest He sends (to their bodies) for a term appointed. Verily in this are Signs for those who reflect.
What! Do they take for intercessors others besides Allah? Say: "Even if they have no power whatever and no intelligence?"
Say: "To Allah belongs exclusively (the right to grant) intercession: to Him belongs the dominion of the heavens and the earth: In the End, it is to Him that ye shall be brought back."
Excerpted from The Quran6:59-62; 39:41-44