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Surah 7. Al-A'raf
Ayah 187 - 188
١٨٧. يَسْـَٔلُونَكَ عَنِ ٱلسَّاعَةِ أَيَّانَ مُرْسَىٰهَا ۖ قُلْ إِنَّمَا عِلْمُهَا عِندَ رَبِّى ۖ لَا يُجَلِّيهَا لِوَقْتِهَآ إِلَّا هُوَ ۚ ثَقُلَتْ فِى ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضِ ۚ لَا تَأْتِيكُمْ إِلَّا بَغْتَةً ۗ يَسْـَٔلُونَكَ كَأَنَّكَ حَفِىٌّ عَنْهَا ۖ قُلْ إِنَّمَا عِلْمُهَا عِندَ ٱللَّهِ وَلَـٰكِنَّ أَكْثَرَ ٱلنَّاسِ لَا يَعْلَمُونَ
١٨٨. قُل لَّآ أَمْلِكُ لِنَفْسِى نَفْعًا وَلَا ضَرًّا إِلَّا مَا شَآءَ ٱللَّهُ ۚ وَلَوْ كُنتُ أَعْلَمُ ٱلْغَيْبَ لَٱسْتَكْثَرْتُ مِنَ ٱلْخَيْرِ وَمَا مَسَّنِىَ ٱلسُّوٓءُ ۚ إِنْ أَنَا۠ إِلَّا نَذِيرٌ وَبَشِيرٌ لِّقَوْمٍ يُؤْمِنُونَ
[187-188] These people ask you: "Well, when is the Hour of Resurrection coming?" Say, "Its knowledge is with my Lord alone: He Himself will disclose it at the proper time: that Hour will weigh heavily on the heavens and the earth. It will come on you all of a sudden. " They ask you about it as though you have been in search for it. Say; "Its knowledge is with Allah alone, but most of the people do not know this. " Tell them, O Muhammad, "I have not the power to bring any good to or avert any harm from myself: only that happens which Allah wills. Had I the knowledge of the unseen, I would have acquired many benefits for myself and would never have suffered any harm.145 I am merely a Warner, and a bearer of good news to those who believe in what I say."
145That is, "I cannot tell you the exact time of Resurrection because I myself do not know anything about the unseen. Had I possessed any knowledge of the future, I would not have suffered any harm because I would have avoided it and achieved many benefits because of my fore knowledge. Therefore it is very foolish on your part to ask me about it merely to test my Prophethood."