Quran 7:187 — The Purgatory (Al-A'araf)

They ask you about the end of the world (the Hour),* and when it will come to pass. Say, "The knowledge thereof is with my Lord. Only He reveals its time.* Heavy it is, in the heavens and the earth. It will not come to you except suddenly."** They ask you as if you are in control thereof. Say, "The knowledge thereof is with GOD," but most people do not know.

[7:186] Whomever GOD commits to straying, there is no way for anyone to guide him. He leaves them in their sins, blundering.

[7:188] Say, "I have no power to benefit myself, or harm myself. Only what GOD wills happens to me. If I knew the future, I would have increased my wealth, and no harm would have afflicted me. I am no more than a warner, and a bearer of good news for those who believe."