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Surah 7. Al-A'raf
Ayah 187 - 188
187 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
188 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."