This video gives a brief summery of how the Quran was preserved and is unchanged till today.
The preservation of the Quran - Adnan Rashid - LDM Show
Here are just a few examples of non-Muslim religious and textual scholars who testify to the preservation of the Qur’an:
A.T. Welch, a non-Muslim Orientalist, writes:
“For Muslims the Qur’an is much more than scripture or sacred literature in the usual Western sense. Its primary significance for the vast majority through the centuries has been in its oral form, the form in which it first appeared, as the “recitation” chanted by Muhammad to his followers over a period of about twenty years… The revelations were memorized by some of Muhammad’s followers during his lifetime, and the oral tradition that was thus established has had a continuous history ever since, in some ways independent of, and superior to, the written Qur’an… Through the centuries the oral tradition of the entire Qur’an has been maintained by the professional reciters (Qurraa). Until recently, the significance of the recited Qur’an has seldom been fully appreciated in the West.” Leading Orientalist Kenneth Cragg reflects that:
“…this phenomenon of Qur’anic recital means that the text has traversed the centuries in an unbroken living sequence of devotion. It cannot, therefore, be handled as an antiquarian thing, nor as a historical document out of a distant past. The fact of hifdh (Qur’anic memorization) has made the Qur’an a present possession through all the lapse of Muslim time and given it a human currency in every generation, never allowing its relegation to a bare authority for reference alone.” Quotes taken from Many Prophets, One Message
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