Someone might ask: You say the Prophet (SAW) was unlettered and could not read or write. Then, how can you trust that his scribes actually accurately wrote what he dictated to them? What if they twisted his words?
There are two responses to this question: 1) reasons we can trust the Quran as it was written, and 2) proof that this line of argumentation is absurd.
First: The reasons we can trust the Quran as it was written are the following:
- Even if the Prophet (SAW) could not read himself, he could get the scribe to dictate the text back to him and correct anything that needed correction.
- The Prophet (SAW) did not only have one scribe but multiple scribes, and in fact, almost no verse in the Quran was written by one scribe alone. Thus, there was always a check for any scribe, and it would be impossible for one person to introduce an error without others correcting him.
- Writing was only one avenue of preserving the Quran. There was a whole another avenue: memorization. Many companions memorized the Quran from the Prophet (SAW), and mistakes in writing would be easily caught by the memory of those who memorized the Quran.
Second: This line of argumentation is absurd because it entails distrusting every text of which you do not have an original manuscript. That is because the question relies on the assumption that a text is untrustworthy simply because the Prophet did not himself write it or read it with his eyes and ignores all other contextual reasons to trust the writing of the text.
But, this objection that the originator did not write it himself would apply to all subsequent copies of a text anyway!
For example, even if the Prophet (SAW) wrote the Quran personally, that would still leave the fact that scribes after him would have to copy the Quran into different manuscripts to preserve it. The originals would not survive 1400 years simply because almost nothing from that time survives.
Thus, even if the Prophet was literate and wrote his own copy of the Quran, one would still need to rely on manuscripts that were not personally written or reviewed by him but that were based on his copy. So, even if the Prophet wrote the Quran himself, it would still come to us through intermediaries and in copies not directly written by the Prophet.
In fact, almost no book a person reads is the original version by the writer. Books people read are always through intermediaries. If someone rejects this as reliable, then he would be forced to reject almost every book in existence, historically and contemporarily. This is absurd, and no serious historian or rational person would entertain the idea.
If the person says that sometimes books the author did not write personally can be reliable depending on the context and how strongly they are confirmed, then he has retracted his original position. The same logic would apply even if the first writing of the text was dictated and not written personally. It would still depend on context.
So, it does not matter whether the Prophet was unlettered or whether he personally wrote down the Quran. What matters is whether there are contextual reasons to confirm the writings of the Quran, and there are extremely strong contextual reasons as mentioned above.