Short answer
It was kept in two ways at once, from the first day. Each passage was learned by heart, word for word, and recited in prayer. Each was also written down by scribes as it came. The Prophet (ﷺ) told them where every passage belonged. Once a year the angel Gabriel went over the whole text with him, and twice in his last year. Within two years of his death, Abu Bakr, the first leader after him, had it gathered into one volume. He used the written pieces and the memories of men. Less than twenty years after his death, Uthman, the third leader, sent copies of that volume to every great city. Some of the oldest leaves that survive, kept in Birmingham in England, carry today's text, apart from small points of spelling. The Qur'an promised that God (﷾) would guard it, and history shows the promise kept.
Full explanation
The promise
The Qur'an says that God (﷾) sent down the Message, the Qur'an, and will guard it. It also tells the Prophet (ﷺ) not to hurry his tongue as the revelation comes. Gathering it and reciting it, it says, is God's (﷾) work. So this is a claim about history, and history can check it. The Qur'an also offers a test any reader can apply: had it come from anyone but God (﷾), people would find much discrepancy in it.
“We have, without doubt, sent down the Message; and We will assuredly guard it (from corruption).”
“Move not thy tongue concerning the (Qur'an) to make haste therewith. It is for Us to collect it and to promulgate it: But when We have promulgated it, follow thou its recital (as promulgated): Nay more, it is for Us to explain it (and make it clear):”
“Do they not consider the Qur'an (with care)? Had it been from other Than Allah, they would surely have found therein Much discrepancy.”
Memorised and written while he lived
The Qur'an came in portions over twenty-three years. His Companions, the believers who lived beside him, learned each portion by heart and recited it in their prayers. They lived in a culture that carried long poems and whole family trees in memory. Scribes wrote each passage down as it came, and Zayd ibn Thabit was the chief scribe. Sahih al-Bukhari is a collection of trusted reports about the Prophet (ﷺ). It records that Gabriel went over the whole text with him every year, and twice in his final year. Later, Uthman, the third leader of the Muslims, would not move a single verse from the place where it had been set.
Abu Hurayra reports that Gabriel went over the Qur'an with the Prophet (ﷺ) once every year, and twice in the year he died.
Zayd ibn Thabit reports that after many who knew the Qur'an by heart were killed at Yamama, Abu Bakr asked him to gather the Qur'an into one volume, reminding him that he used to write down the revelation for the Messenger of Allah. Zayd collected it from written pieces and from the memories of men, and the finished copy passed from Abu Bakr to Umar and then to Hafsa.
Ibn al-Zubayr asked Uthman why he kept writing a verse (2:240) whose ruling had been replaced by another. Uthman answered that he would not move anything of the Qur'an from its place.
Collected within two years
Many Companions who knew the Qur'an by heart were killed at the battle of Yamama. This was less than two years after the death of the Prophet (ﷺ). Umar, a leading Companion, urged Abu Bakr, the first leader of the Muslims after the Prophet (ﷺ), to have the Qur'an gathered. Abu Bakr gave the task to Zayd. Zayd gathered it from the written pieces and from the memories of men. The finished volume passed from Abu Bakr to Umar and then to Hafsa, Umar's daughter and one of the Prophet's (ﷺ) wives.
Zayd ibn Thabit reports that after many who knew the Qur'an by heart were killed at Yamama, Abu Bakr asked him to gather the Qur'an into one volume, reminding him that he used to write down the revelation for the Messenger of Allah. Zayd collected it from written pieces and from the memories of men, and the finished copy passed from Abu Bakr to Umar and then to Hafsa.
Uthman's copies
As Islam spread, soldiers from Syria and Iraq argued over how the Qur'an was recited. Hudhayfa, a Companion, warned Uthman to act before Muslims differed over their Book as Jews and Christians had. Uthman had copies made from Hafsa's volume and sent one to each province, meaning each region of the Muslim lands. He did this less than twenty years after the death of the Prophet (ﷺ). Thousands who had heard the Qur'an from him were still alive. Ali, who later led the Muslims himself, said he would have done the same.
Anas reports that Hudhayfa ibn al-Yaman, alarmed at how the soldiers of Syria and Iraq differed in reciting the Qur'an, urged Uthman to save the community before it differed over its Book as the Jews and Christians had. Uthman borrowed the collected sheets kept by Hafsa, had Zayd ibn Thabit and three men of Quraysh copy them, telling the three that wherever they differed with Zayd they should write in the dialect of Quraysh, in which the Qur'an was revealed, returned the sheets to her, sent a copy to every province, and ordered all other written Qur'anic material to be burned.
Suwayd ibn Ghafala reports that Ali said to speak only good of Uthman about the copies of the Qur'an, because he acted only after consulting the Companions, and that had Ali been in charge he would have done the same. Ibn Hajar calls the chain of this report sound.
The oldest manuscripts
Manuscripts are old handwritten copies. Two leaves in Birmingham are written on parchment, a prepared animal skin. The parchment has been radiocarbon dated (tested for age) to between 568 and 645. That span covers the lifetime of the Prophet (ﷺ). The leaves carry parts of Surahs (chapters) 18 to 20. Apart from small points of spelling, the words are those of the Qur'an in any Muslim's hands today. Sir William Muir was a nineteenth-century Christian historian hostile to Islam. Even he judged that there is probably no other book in the world that has kept so pure a text for twelve centuries.
Two parchment leaves carrying parts of Surahs 18 to 20 in early Hijazi script. In 2015 the Oxford Radiocarbon Accelerator Unit dated the parchment to between 568 and 645 CE, with 95.4 per cent probability, a span that covers the Prophet's (ﷺ) lifetime (c. 570-632). Apart from small points of spelling, the text on the leaves is the text of those surahs as the Qur'an has them today.
Muir, a Christian historian and a sharp critic of Islam, judged that there is probably no other book in the world that has kept so pure a text for twelve centuries.
- His lifetime
Learned by heart
The Qur'an came to the Prophet (ﷺ) in parts over twenty-three years. His Companions, the believers around him, learned each part word for word and recited it in prayer. Every year the angel Gabriel went over all of it with him.
- His lifetime
Written down
Scribes, led by Zayd ibn Thabit, wrote each passage down as it came. The Prophet told them where every passage belonged.
- Within 2 years
Gathered into one volume
Abu Bakr, the first leader after the Prophet, had Zayd gather it into one volume, from the written pieces and from the men who knew it by heart. Zayd added nothing of his own.
- Within 20 years
Copied for every province
As Islam spread, Uthman, the third leader, had copies made from that volume and sent one to each province. Thousands who had heard the Qur'an from the Prophet were still alive.
- Today
The oldest leaves match
Two very old leaves kept in Birmingham hold parts of chapters (surahs) 18 to 20. A scientific test of their age (radiocarbon dating) gives a range of dates that covers the Prophet's lifetime. Their words are the words of the Qur'an Muslims read today.
By contrast, the earliest surviving list of exactly the twenty-seven books of the New Testament comes from 367, more than three centuries after Jesus.
Seven ways of reciting
The Prophet (ﷺ) said the Qur'an was revealed to be recited in seven ways, so people may recite whichever is easier. He said this when Umar brought him a Companion who recited a surah differently from the way Umar had learned it. The Prophet (ﷺ) heard each man recite, and said of both that it was revealed this way. Scholars explain that this made recitation easy for tribes who spoke differently. They differ on how the seven ways relate to the readings recited today. A reading is a recognised way of reciting, handed down from teacher to student. Hafs and Warsh are two of the readings used around the world. Muslim scholars agree that these readings reach back to the Prophet (ﷺ) through unbroken chains of reciters. They also agree that each reading fits the written text of at least one of Uthman's copies. And they agree that the readings never contradict each other: where the wording differs, both readings were revealed.
Umar heard Hisham ibn Hakim recite Surat al-Furqan differently from the way he had learned it and brought him to the Prophet (ﷺ). The Prophet had each recite, said of both readings that the surah was revealed that way, and said the Qur'an was revealed to be recited in seven ways, so recite whichever is easier.
Set beside the Bible
The Qur'an was gathered within two years of the death of the Prophet (ﷺ), from men who had heard it from him. The earliest surviving list of exactly the twenty-seven books of the New Testament comes from the year 367. It is a letter by Athanasius, a bishop of Alexandria. That is more than three centuries after Jesus, when no eyewitness was alive. Modern Bibles mark whole passages as absent from the oldest manuscripts. One example is the last twelve verses of Mark. The two oldest complete Greek copies of Mark end at 16:8.
Athanasius, bishop of Alexandria, lists the books he counts as scripture. His New Testament list is the twenty-seven books of today's New Testament, the earliest surviving list of exactly these books and no others.
On Mark 16:9-20, reports that the last twelve verses are absent from the two oldest Greek Bibles that survive in large part, Codex Sinaiticus and Codex Vaticanus, and from other early witnesses; that Eusebius and Jerome state the verses were missing from almost all the Greek copies known to them; that some manuscripts carry a different, shorter ending instead; and concludes that the Gospel as we have it from the earliest evidence ends at 16:8.
The objection answered
Sahih al-Bukhari 4987 — Kitab Fada'il al-Qur'an (Virtues of the Qur'an), hadith 4987
Anas reports that Hudhayfa ibn al-Yaman, alarmed at how the soldiers of Syria and Iraq differed in reciting the Qur'an, urged Uthman to save the community before it differed over its Book as the Jews and Christians had. Uthman borrowed the collected sheets kept by Hafsa, had Zayd ibn Thabit and three men of Quraysh copy them, telling the three that wherever they differed with Zayd they should write in the dialect of Quraysh, in which the Qur'an was revealed, returned the sheets to her, sent a copy to every province, and ordered all other written Qur'anic material to be burned.
Cited for
Uthman burned every copy but his own, so rival Qur'ans must have been destroyed and the text we have is his edition.
The response
Muslim scholars explain that what was burned was the Companions' personal working copies and scraps, some with their owners' own notes. Uthman's copies were made from the volume gathered under Abu Bakr. Zayd had gathered that volume from both the written pieces and the memories of men. Uthman told the three copyists from Quraysh that wherever they differed with Zayd, they should write in the dialect of Quraysh. This was the Prophet's (ﷺ) own tribe, and the Qur'an had come down in its dialect. Muslim scholars explain that this settled how words were written, not what the Qur'an says. Uthman acted in public, while thousands who had learned the Qur'an from the Prophet (ﷺ) were still alive. Ali said Uthman acted only after consulting the Companions, and that he would have done the same.
Where it lands — Uthman copied the text already gathered under Abu Bakr; he did not make a new one.
Perspectives
Uthman's copy replaced the others
Many sceptics point out that the caliph Uthman sent one copy of the Qur'an to every province, and had the other written copies burned. They ask how anyone can know what the burned copies said.
Uthman ordered all other written copies burned, so no one can know what they held.
Rebuttal
The same report says what Uthman's copy was made from. It was the volume Abu Bakr had gathered from written pieces and from the memories of men, kept by Hafsa and given back to her. The burning ended quarrels over how to recite. It did not change the text, which many people knew by heart. Ali said Uthman acted only after asking the Companions, and that he would have done the same. And leaves dated to the Prophet's (ﷺ) own time carry today's text.
Fixed only two centuries later
A school of critics arose in the 1970s, led by John Wansbrough. They argued that the Qur'an took its fixed form slowly, about two centuries after the Prophet (ﷺ).
John Wansbrough argued that the Qur'an's fixed text emerged over about two centuries. It was not final, he said, until around the end of the eighth century.
Rebuttal
Wansbrough wrote before the radiocarbon tests. They dated the Birmingham leaves, which carry today's text, to between 568 and 645. A leaf of the Sanaa parchment was dated, with high probability, to before 671. Its erased text has the same verses within each surah, almost always in the same order. So today's text was in use within the first century of Islam, not two centuries later.
The Sanaa parchment shows a different Qur'an
A parchment found in Sanaa, in Yemen, has an older text washed off beneath today's text. Some critics say this erased text shows an earlier, different Qur'an.
The erased text under the Sanaa parchment differs from today's Qur'an, so the Qur'an was once different.
Rebuttal
Its editors studied it word by word. Within each surah, the surviving lower text has the same verses in the same order, with two exceptions: one pair of verses is swapped, and one verse that almost repeats another is missing. The other differences are small words and phrases, and the surahs come in a different order. The editors judge it a Companion's personal copy, of the kind the Muslim sources say existed before Uthman's copies and were withdrawn. And they conclude that today's text is the more faithful to the Prophet's (ﷺ) recitation.
Verses were lost
Critics point to reports of verses that were once recited but are not in the Qur'an today. The best known is Umar's report of a verse on stoning.
Umar said a verse on stoning was revealed and recited, yet it is not in the Qur'an. So verses were lost.
Rebuttal
The Qur'an itself says that God (﷾) replaces some revelations and causes some to be forgotten (2:106). It tells the Prophet (ﷺ) he will not forget, "Except as Allah wills" (87:6-7). Ibn Kathir, a 14th-century commentator, reports that some commentators read that exception as what God (﷾) willed to lift. So what was lifted, God (﷾) lifted while the revelation was still coming. The Book said so itself. It was not lost later by those who kept it. Umar's own words fit this. He says the verse was recited and memorised, and that the Prophet (ﷺ) acted on its ruling. He does not blame anyone for losing it. He feared that people would one day drop the ruling because they would not find the verse in the Book. In the Prophet's (ﷺ) last year Gabriel went over the Qur'an with him twice, and soon after his death Abu Bakr had it gathered from writing and memory.
Few dots, so the first reading is lost
Critics note that the oldest copies have few of the dots that tell Arabic letters apart. They say no one can know how the text was first read.
The oldest manuscripts have few dots. Many Arabic letters share one shape, so no one can know how the text was first read.
Rebuttal
It is true that the earliest copies mark only some of the dots. But the Qur'an was never kept by ink alone. Its name means recitation. It was learned by heart and heard aloud more than it was read, and the written copy helped people who already knew the words. Where a word without dots can be read in more than one way, only certain readings are recited. Each must fit Uthman's copies, be sound Arabic and come down by a sound chain of reciters from the Prophet (ﷺ). A detailed study of two readings recited today, Hafs and Warsh, found that very few of their differences make any real difference to the meaning.
What the historical record shows
The sources describe a text memorised and written in the lifetime of the Prophet (ﷺ). It was gathered within two years and copied for every province within twenty.
After many reciters were killed at Yamama, Abu Bakr had Zayd ibn Thabit gather the Qur'an. Zayd used the written pieces and the memories of men.
Uthman had copies made from Hafsa's volume and sent one to each province, to stop disputes over recitation.
Ali approved of what Uthman did with the copies of the Qur'an.
The parchment of the Birmingham leaves is dated by radiocarbon to between 568 and 645. The leaves carry today's text of Surahs 18 to 20, apart from spelling.
Sir William Muir was no friend of Islam. He judged that there is probably no other book in the world that has kept so pure a text for twelve centuries.
The first list that survives of exactly the New Testament's twenty-seven books dates from 367. No eyewitness of Jesus was alive by then.
The Islamic perspective
God (﷾) revealed the Qur'an to the Prophet (ﷺ) and promised to guard it. He kept it in two separate ways, side by side, from the start: in memory and in writing.
The Qur'an promises that God (﷾) Himself will guard it from corruption.
The Qur'an tells the Prophet (ﷺ) that gathering and reciting the revelation is God's (﷾) work.
The Islamic method holds that the Prophet (ﷺ) set the place of each verse. And Gabriel went over the whole text with him every year.
The Prophet (ﷺ) taught that the Qur'an may be recited in seven ways.
The Prophet (ﷺ) approved two different recitations of the same surah as both revealed.