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Surah 16. An-Nahl
Ayah 89
89وَيَوْمَ نَبْعَثُ فِى كُلِّ أُمَّةٍ شَهِيدًا عَلَيْهِم مِّنْ أَنفُسِهِمْ ۖ وَجِئْنَا بِكَ شَهِيدًا عَلَىٰ هَـٰٓؤُلَآءِ ۚ وَنَزَّلْنَا عَلَيْكَ ٱلْكِتَـٰبَ تِبْيَـٰنًا لِّكُلِّ شَىْءٍ وَهُدًى وَرَحْمَةً وَبُشْرَىٰ لِلْمُسْلِمِينَ
[89] (O Muhammad, warn them of) the Day when We shall call a witness from among every community to testify against it. And We shall call you to testify against these people; (that is why) We have sent down .to you this Book which makes plain everything86 and is guidance, blessing and good news to those who have surrendered themselves entirely.87
86The Qur'an makes manifest everything on which depends guidance or deviation, success or failure: whose knowledge is essential for following the Right Way: which clearly distinguishes Truth from false hood.
In this connection one should guard against that meaning of this sentence and the like in the Qur'an according to which some people interpret "everything" to mean "the knowledge of all sciences, arts, etc.," and in order to prove the correctness of their interpretation, they have to pervert the real meaning of the Qur'an.
87This Book is a guidance for those who surrender to it as a Divine Book and follow it in every aspect of life. Then it will bring Allah's blessings upon them, and will give them the good news that they will come out successful in the Court of Allah on the Day of Judgment. Or. the contrary, those people who reject it shall not only be deprived of guidance and blessing but will also find it as a testimony against themselves on the Day of Resurrection when Allah's Messenger will stand up to testify against them. This Book will prove to be a strong argument against them, for Allah's Messenger will say that he had conveyed its Message which made manifest the distinction between Truth and falsehood.