Ankebut 47-48:

• İşte size bu Kitab'ı indiriyoruz. Önceden kendilerine Kitap verilmiş ve (bu ilahi vahyi kabul konusunda samimi) olanlar ona inanırlar. Şu (Mekke) halkında da ona inananlar vardır. Ancak bile bile küfürde ısrar edenler bu Kitab'ı reddederler.  Hem sen (Ey Muhammed(sav)) bu Kitaptan önce herhangi bir kutsal kitap okumuş veya kendi ellerinle yazmış değildin. Öyle olsaydı, batıl iddia peşinde koşanlar şüphe duyardı.
  (
  The basis of the argument in this verse is that the Holy Prophet was unlettered. His compatriots and his kinsmen among whom he had spent his whole life, from birth to old age, knew fully well that he had never read a book nor ever handled a pen. Presenting this actual fact Allah says: "This is a proof of the fact that the vast and deep knowledge of the teachings of the Divine Books, of the stories of the former Prophets, of the beliefs of the various religions and creeds, of the histories of the ancient nations, and the questions of social and moral and economic life, which is being presented through this unlettered, illiterate man could not have been attained by him through any means but Revelation. If he had been able to read and write and the people had seen him reading books and undertaking serious studies, the worshipers of falsehood could have had some basis for their doubts, that he had acquired the knowledge not through Revelation but through study and reading. But the fact of his being absolutely illiterate has left no basis whatever for any such doubt. Therefore, there can be no ground, except sheer stubbornness, which can be regarded as rational in any degree for denying his Prophethood."   ET
  
  )