The Qur’an is a compilation of Divine Speeches of God in the form of Classical Arabic which the modern man has printed in a book that anyone can hold and read. The book (mushaf) that you hold is NOT the Qur’an. The recitation in Classical Arabic IS the Qur’an. The Qur’an was revealed to the last Messenger of God (Muhammad s.a.w) by speech, not by writing. That is why it is compulsory for any Muslim throughout history, generations after generations, to recite the Qur’an using the ORIGINAL Arabic speech and with the original recitation style (tajweed) as when it was first revealed 1500 years ago!
The Quran was made public right at the beginning. It was not meant for private access only by scholars or religious leaders. It was a tradition since the very first generations of Muslims and subsequent generations throughout time to produce millions who memorized the Qur’an in the original language cover-to-cover. The original language of the Quran is still preserved now as it was 1500 years ago.
Recitation of the Qur’an in English is not a recitation of the Qur’an. Similarly, reading a translation of the Qur’an is NOT reading the Qur’an. Translators can be biased. People can get influenced by the translators. A translator can make mistakes. He can hide what he doesn’t like. He can change the meanings to something else according to what his desires.
If many translations of a single “Holy Book” were produced but the original book written in the original language was long gone, there is no way for future generations to know exactly what the original messages in the “Holy Book” were. Each person will only understand what the interpreter understood that was translated into their own language (not the original language of the “Holy Book”). Future generations are at the mercy of past interpreters.
Let say revelations were based on one or two handwritten copies of a holy book by two or three people and was handwritten copied and translated by several people from different land and culture. The copies were privately kept. The Public has no access to this "Holy" book. The "layman" person only knew the religion coming from the mouths of these "Holy" men who kept their translated copies of the "Holy" book.
After many generations of copying and translating into individual languages and by the time it reached our generation there will be multiple versions of translated copies of the “Holy Book”. The original “Book” with the original classical language and culture was forever gone. Multiple version can occur when the person who translated the book change the texts either accidentally, carelessly, forgetfully or purposely without the mass population knowing about it. They do not have photo-copying machine in those days. When this lone person copied a thick “holy book” via handwriting without any government appointed editorial committee to check on his copying, the chances of the texts deviating from the original were significantly high.
As for the Quran, the original messages were not at the mercy of translated copies. All scholars who want to translate the Quran into individual languages will refer back to the original classical language of the Quran. Apart from word by word translation, scholars produced volumes of Tafseer of the Quran in an effort to really understand the messages. Each Tafseer will be based on the understanding and opinions of the scholar who wrote it. Therefore there is a clear distinction between the original Arabic Quran and the many Tafseer Books by Scholars. A Holy Book should not be mixed up with the writings of men.
The effectiveness of the tradition of memorization of the Quran across all generations and nations of Muslims:
What if a phrase is memorized by a person and checked by many other people who also memorized the same phrase? Example, thousands memorized the phrase “The quick brown fox jumps over the lazy dog”. If someone saying the phrase as “The quick round ox jumps over the lazy hog”, immediately many people will tell him that he made a mistake.
Hence, reciting the speeches in the original language and out of the memory of millions (accessible to the mass public), is the path where the Qur’an has been preserved since the very beginning of revelations. If today, all the “Holy Books” of the world are removed (deleted from computer storage, libraries or Museums, etc) to the point where not a single “Holy Book” remains anywhere on earth, the Muslims can re-produce another original Qur’an as fast as the next day, with no argument among them regarding the accuracy of the written speech. Why is this so?
Suppose you get ten “Hafizs” (one who has memorised the Qur’an) from China, and another ten “Hafizs” from Australia. Let one “Hafiz” recites one Surah from memory, and if he makes a mistake, the others will immediately correct him. Each one take his turn, and if he makes a mistake, the others will correct him too. All of them memorized exactly the same Qur’an. If you get 10,000 Hafizs from different parts of the world, they will have the same recitations cover to cover too.
If you take one MuS-haf that was printed today and bring it to where one of the ancient MuS-haf was kept (eg. Al-Hussein Mosque, Cairo, Egypt) and compare them side by side, you will see that the “uthmani” writings matches on both Mus’hafs. The modern Mus’haf, however, has dots and vowels printed on the letters to help the modern non-Arabic speaking person recite. This is one prove of the preservation of the Quran. The main medium of preservation was still from the memory of millions of Hafiz.
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إِنَّا نَحۡنُ نَزَّلۡنَا ٱلذِّكۡرَ وَإِنَّا لَهُ ۥ لَحَـٰفِظُونَ
We have, without doubt sent down the Message; and We will assuredly guard it (from corruption).
[Al-Hijr 15:9]