On the other hand, there is no such doubt about the Glorious Qur'an. It contains nothing but the Revelations received by the Prophet Muhammad (pbuh). The Revelations came to him in fragments, from time to time. As soon as he received any, he used to communicate it to his Companions and ask them not only to commit it to memory, but also to write it down. Muhammad (pbuh) used to indicate in a precise manner the place to which the Revelation belonged. Thus the complete Qur'an was committed to writing and also preserved in the
hearts of hundreds of Muslims in the life time of the Prophet.
After the demise of the Prophet, Abu Bakr, the first Caliph, charged Zaid ibn Thabit with the task of preparing an authentic copy of the entire Text in the form of a book. The Companions of the Prophet wrote the Revelations that had come to the Prophet on parchments or pieces of leather. Zaid ibn Thabit collected all these and, after comparing them with what the followers of the Prophet had learnt by heart, compiled a copy, called Mushaf (bound leaves), about the genuineness or correctness of which there was absolutely no doubt.
At the order of 'Uthman, the third Caliph, seven copies of the Mushaf edition of the Glorious Qur'an, again confined by the memory of those who had learnt it by heart (hafiz), were prepared and sent to the different centers of the vast Islamic world. One of these seven copies is still in existence in Tashkent. The Czarist government of Russia had published it with a facsimile reproduction; and we see that there is a complete identity between this copy and the text otherwise in use all over the world. The same is true of the other extant MSS of the Qur'an, complete or fragmentary, dating from the first century of the Muslim era.
From the time of the Prophet to our own time the practice of learning the whole of the Qur'an by heart has continued unbroken, and the number of hafiz can now be counted by hundreds of thousands all over the world. The result is that no scholar, Eastern or Western, Muslim or non-Muslim, has ever cast any doubt on the purity of the text of the Glorious Qur'an. Even such an unfriendly critic as Sir William Muir writes about the Qur'an:
"There is probably in the world no other book which has remained twelve centuries with so pure a text."
 Sir William Muir, The Life of Mohamet, Introduction, p.l8.