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Surah 34. Saba
Ayah 7 - 8
7 وَقَالَ ٱلَّذِينَ كَفَرُوا۟ هَلْ نَدُلُّكُمْ عَلَىٰ رَجُلٍ يُنَبِّئُكُمْ إِذَا مُزِّقْتُمْ كُلَّ مُمَزَّقٍ إِنَّكُمْ لَفِى خَلْقٍ جَدِيدٍ
8 أَفْتَرَىٰ عَلَى ٱللَّهِ كَذِبًا أَم بِهِۦ جِنَّةٌۢ ۗ بَلِ ٱلَّذِينَ لَا يُؤْمِنُونَ بِٱلْـَٔاخِرَةِ فِى ٱلْعَذَابِ وَٱلضَّلَـٰلِ ٱلْبَعِيدِ
[7-8] The disbelievers say to the people, "Shall we point out to you a man who gives the news that when your body will have been scattered into particles, you will be resurrected once again? No one knows whether this man forges a lie in the name of Allah or is mad."10
10The chiefs of the Quraish knew full well that it was extremely difficult for the common people to accuse Muhammad (upon wham be Allah' peace) of being a liar, for the whole nation knew that he was a completely truthful person, and no one had ever heard a lie from him all his life. Therefore, they presented their charge against him before the people like this: 'When this person utters an impossible thing like the life-after-death from his mouth, he is either uttering (God forbid) a falsehood deliberately, or he is mad.' But this accusation of madness also was as absurd as of falsehood, for a stupid person only could admit that such a wise and intelligent man as the Holy prophet could be mad. That is why Allah did not feel it was necessary to refute their absurd charge by an argument, and only made mention of their wonder which they expressed at the possibility of the life-after-death