There are a few different ways to prove that the Qur'an is the word of God, which has always been true and has never been subjected to change or distortion.
These proofs can be classified into three types:
1) The way the Qur'an was transmitted throughout the centuries,
2) Some challenging verses within the Qur'an itself, and the periodic,
3) Modern-day discoveries in the universe that were first mentioned in the Qur'an more than fourteen centuries ago.
Unlike the Bible and Old Testament that have been subject to innumerable translations, doubtful and spurious transmissions, and corruptions at the hands of clerics up till now (with the “gender sensitive” versions coming out these days), the Qur'an was transmitted to us in an unprecedented and unique manner according to rigorous rules of transmission. The Qur'an was revealed to the Prophet Muhammad (peace be upon him) via the angel Gabriel, and the Prophet subsequently memorized the whole scripture.
Thousands of the Companions of the Prophet learned the Qur'an directly from the Prophet (pbuh). They memorized it and were known in Islamic history as huffaadh (the memorizers and preservers of the Qur'an). Moreover, a number of Companions wrote it down during the lifetime of the Prophet (peace be upon him), and it was compiled in its entirety immediately after his death.
The following generation of Muslims learned the Qur’an directly from the Companions. Thus the chain of teaching and learning through direct contact continued systematically, methodically, and meticulously until the present age.
Additionally, several of the Companions of the Prophet Muhammad (peace be upon him) were appointed as scribes to record the words of the revelation directly from the Prophet himself on parchment, leather, or whatever else was available. The most famous of these scribes was Zayd ibn Thabit, who also memorized the entire Qur’an, and he formed with the others a community of huffaadh that can be compared to academic societies of our present time.
We know the Qur’an was recorded in totality during the lifetime of the Prophet (pbuh) and the different surahs (chapters) personally arranged by him. Many copies of the text were used for study and teaching, even in Mecca before the Hijrah, the migration to Medina.
The entire Qur’an was written down during the lifetime of the Prophet Muhammad, and trusting the fact that many scholars knew it by heart, it was not collected in one volume. It was personally arranged by him, and the Muslims memorized it in the same order. The companion Uthman reported that whenever a new verse was revealed, the Prophet would immediately call a scribe to record it. He would instruct the person to put the specific verse or verses in a particular chapter.
Furthermore, every year during the month of Ramadan, the Prophet would recite the whole Qur’an from beginning to end in its present-day arrangement, and everyday people could hear it from his own lips in the mosque. Its sequence is no mystery. Many of the Companions not only memorized it completely, they also wrote it down and even added commentary (tafseer) on their own personal copies. When the Prophet passed away, the whole Qur’an was already written down, but it was not yet compiled in book form.
During the rule of the first Caliph Abu Bakr, there was a rebellion among some distant Arab tribes that resulted in a series of fierce battles. In one particular battle, a number Companions who had memorized the Qur’an were killed. The Companion Omar worried that the knowledge of the Qur’an was in danger, thus he convinced Abu Bakr that the Qur’an should be compiled into book form as a means of preserving it once and for all.
Zayd bin Thabit was entrusted with this important task. Zayd followed strict methods in his compilation and had dozens of other huffaadh recheck his work to ensure its accuracy. Abu Bakr, who had also committed the entire Qur’an to memory, approved of the final product. After Abu Bakr passed away, the copy was passed to the Caliph ‘Omar, and then Uthman.
However as the Muslim world expanded into lands where the people spoke Arabic as a second language, the new Muslims had a difficult time learning the correct pronunciation of the text. The Caliph Uthman consulted other Companions, and they agreed that official copies of the Qur’an should be inscribed using only the pronunciation of the Quraysh tribe, the Arabic dialect that the Prophet spoke.
Zayd bin Thabit was again given this assignment, and three other huffaadh were assigned to help him in the task. Together, the four scribes borrowed the original, complete copy of the Qur’an, duplicated it manually many times over, and then distributed them to all of the major Muslim cities within the empire. Two of these copies still exist today: one is in Istanbul and the other in Tashkent.
One must keep in mind that in traditional learning in the Arab world, transmission was based upon an oral tradition as well as a written one; the Arabs (and later all Muslims) excelled in accurately reporting scripture, poetry, aphorisms, etc. through the generations without change. Similarly, the chain of huffaadh was never broken, and thus the Qur'an today has reached us in two forms: the memorized version transmitted through the scholarly chain, and the written version based upon the Companions’ initial recording.
If the Qur’an had been changed, there would be huge discrepancies between these two today, as the Qur’an has reached isolated (and sometimes illiterate) communities through the memorized form of transmission without the written form to correct it. No such discrepancies have ever been recorded or reported. In other words, isolated village A in African Mali and isolated village B in Afghanistan will both produce contemporary huffaadh reciting the same words of the Qur’an, though they did not learn from a similar printing of the scripture nor has there ever been a concerted international effort to rectify would-be discrepancies.
Allah has said in the Qur’an that He alone will protect His book, and indeed He has kept His promise. The Qur’an that we read today contains the same exact words that were revealed to the Prophet Muhammad (peace be upon him) over 1430 years ago. This is quite a miracle, especially when you consider that NO other group of people can say that their book has not been subject to change by the time it reached the present generation.
Only the Qur’an has survived through the centuries unchanged, and the language in which it was revealed, classical Arabic, still enjoys practical usage around the world. While classic English of the 14th century can be understood by only a very few native English speakers, the Qur’an can be understood by the vast majority of Arabic-speaking Muslims. When compared to other scriptures, the Qur’an is unique in these two respects.
Furthermore, from the prolific arts that have accompanied Qur’anic learning and transmission, we can learn of the auspiciousness and honor with which the Muslims have traditionally held the Qur’an. The visual arts of calligraphy and binding, and the vocal art of recitation represent examples of such arts, and from them we can see that veracity of transmission would be understood as a fundamental aspect of Qur’anic reverence.
As regards the proofs within the Qur'an itself, they can be found in the following Qur’anic challenges:
Surah 17, verse 88:
*{Say: If men and jinn should combine together to bring the like of this Quran, they could not bring the like of it, though some of them were aiders of others.}*
And Surah 2, verse 23:
*{And if you are in doubt as to that which We have revealed to Our servant, then produce a chapter like it and call on your witnesses besides Allah if you are truthful.}*
Unanimity of Muslim Scholars
The unanimity of Muslim scholars throughout the ages has also proved that the Quran we have is the same which the Prophet had. The same holds true for some unbiased Orientalist scholars who studied the Quran and found the style and the wording exactly the same as that which was common during the time of the Prophet himself.
Another point that needs reflection is that the Quran contains many scientific miracles that were proven to be correct only recently; it therefore stands to reason that had there been any change in the Quran, such verses or many of them, would have disappeared and even changed, and thus proven wrong.
Oral Transmission
Moreover, the Quran has been handed down through generations and centuries by means of oral transmission alongside the written text and that one of the unique merits of Muslims is their ability of maintaining an unbroken chain proving the authenticity of their texts throughout all these centuries.
Many people memorize the Quran in various parts of the world. All of them meet in one place at one time and recite the same Quran. This leaves no doubt that the Quran we have today is the exact one that was recited 1430 ago when the Prophet was alive.
Language of the Quran
Another logical proof is the decline in the level of the Arabic language and the spoken dialects which we find everywhere in the Arab world.
The deterioration in the level of the spoken Arabic, although affecting the tongues of people, did not in fact come close to the Quranic text. It is because of this that we find the Quranic text being unique in the way it is recited and the way it is written.
It is different in the written form as well as the oral form from the other written or oral texts.
Why? Because it was protected against the factors of time and space.
And for this job to be completed, Allah has enabled many scholars who specialized in the Quranic text whether in the written or the oral form and made their vocation in life to transmit it as exactly as it existed in the Prophet's life.
Quranic Manuscripts
Another physical proof showing the authenticity of the Quran is the large number of Quranic manuscripts dating back to the early times of Islam. One of the manuscripts existing today is the personal copy of the mus-haf (physical copy of the Quran) that belonged to Caliph Uthman Ibn Affan.
This copy still carries the traces of the blood of Uthman who was killed when he was reciting the Quran not long ago after the death of the Prophet. The manuscript has been examined not only by Muslims but also by non-Muslims, and it exists till today as standing evidence of the authenticity of the Quran.
By bringing this manuscript and comparing it with all other manuscripts that have been written through different generations in different parts of the Muslim world, we can see how exactly the same they are.
We can also notice the difference between the text written there and the normal way of writing Arabic words and the question will rise: why did not the normal way of writing affect the way of writing the Quranic text? The simple answer to this is that the uniqueness of the Quran made it very special and as a way of keeping this specialty is keeping it in the same formula it was firstly written.
Challenging the Quran
A long time ago, the Quran challenged people to produce something similar to one verse or ten verses or one surah of it. The challenge was not met and people are still unable to meet the challenge which means the text is still the same miraculous one that was recited during the Prophet's lifetime.
Of course, some biased non-Muslim Orientalists have tried their best to raise misconceptions regarding the authenticity of the Quranic text we have today.
These attempts have been very old indeed and all of them have failed to prove anything.
Source: http://www.readingislam.com