I heard that Muhammad (S.A.W) didn't, so who did?
Click this link to find your answer for your question. http://islamnewsroom.com/news-we-need/112-who-wrote-quran Salam
Its Allah S.W.T., Lord of All worlds
I know that Allah authored it but who wrote it into physical form?
"Didn't Muhammad make up and write the Quran himself?"
No. Muhammad, peace be upon him, did not write the Quran. He was not able to do so, because he was illiterate. He could neither read nor write and there are many who attested to this fact.
"So, if Muhammad did not write the Quran, then WHO DID?"
No person "made up" the Quran. The Quran came down to Muhammad, peace be upon him, from Almighty God (Allah) by way of the angel Gabriel (Jibril in Arabic) and then it was memorized by him and he then in turn, would teach it orally to his companions.
It would be illogical that anyone would WRITE the Quran, because the word "Quran" actually means the "Recitation" (spoken words).
How do you "write sounds" recited words? - You actually only write what you hear. People can only write down what they have heard of the "Quran" (Recital) as Muhammad, peace be upon him, recited it to them.
When we have the Quran in written, book form it is usually referred to as 'scripture' ('mus-haf' in Arabic), although it is still Quran to us. So, while it is of course, possible to write down in book form, what we hear in some form or another, the main point is that Muhammad, peace be upon him, did not make up, fabricated or invent the words in the Quran. And there would be no way he could, as he was illerate and unable to read or write.
So, the question would be correct to ask in this way...
--- "OK - Who first recited the Quran?"
Now this question is easy.
According to the Quran's teachings, it came directly to Muhammad, peace be upon him, from the angel Gabriel (Ar. Jibril), who received it from Almighty God (Allah) and then he recited it to Muhammad, peace be upon him, piece by piece, sentence by sentence, revealing small and large portions of it over a period of 23 years.
The actual assembly and order of verses was never changed by Muhammad, peace be upon him. It was Jibril, the Angel of Allah, who instructed as to what should go where every time more of the Quran was revealed.
"If Muhammad didn't know to read/write, then his friends needed to write Quran (like the Bible) -- right?
NO! Again, they didn't need to write it down to preserve it, althought they did. They all completely memorized it from what they heard. Some of them wrote it down on animal skins, others on large stones or palm leaves, because the prophet Muhammad, peace be upon him, instructed them to do so. So, they did write down what they had heard and that is Quran in written form. They all memorized the Quran for themselves and passed it down the same way they got it. The mouth to ear method of memorizing is still used the same way today for modern Muslims.
-- Could they have misinterpreted or did they possibly modify or add or delet any verses of Quran?"
NO! Allah tells us in the Quran itself, "If you are in doubt about it, bring a book like it" - So, we see that it is a book, yes. But it is not the same as an ordinary book written or made up by humans and that is our main point here.
Get the facts for yourself - straight from the source - from Allah's Quran (in Arabic) Then decide what you think about "Allah's Quran"
Peace be upon you
Salam brother or sister,
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