Quran was honestly transmitted from Prophet Muhammad !

"One important fact that seems now beyond serious doubt is that the Qur’ān, in some form, is a text dating from the earliest history of the Muslim community. The careful work of scholars like Déroche, Sadeghi, Puin, Sinai, Neuwirth, and others on early Qur’ān manuscripts (including the Ṣan‘ā’ manuscripts) has led to the identification and approximate dating of several very ancient copies, or partial copies. These make it quite certain that the Qur’ān—in some form—dates to the seventh century, and is not a text that slowly crystallized in the eighth or ninth century. These early copies, moreover, and work on the Qur’ān’s literary style, also seem to show that many of the different sūrahs into which the Qur’ān is divided are original units, not assemblages of disparate materials as was once thought. These findings are important positive ground gained in our understanding of the Qur’ān’s origin and early development".

Fred Donner "Reflections on the History and Evolution of Western Study of the Qur’ān " 

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