I grew up learning that there are a total of zero differences between any Qur’an anywhere In the world today, and what was revealed by Jibril to Prophet Muhammad. But I now have reason to doubt the perfect preservation of the Qur’an.
A hadith mentioning 2 missing Surahs
Abu Harb b. Abu al-Aswad reported on the authority of his father that Abu Musa al-Ashari sent for the reciters of Basra. They came to him and they were three hundred in number. They recited the Qur'an and he said You are the best among the inhabitants of Basra, for you are the reciters among them. So continue to recite it. (But bear in mind) that your reciting for a long time may not harden your hearts as were hardened the hearts of those before you.
We used to recite a surah which resembled in length and severity to (Surah) Bara'at. I have, however, forgotten itwith the exception of this which I remember out of it: “If there were two valleys full of riches, for the son of Adam, he would long for a third valley, and nothing would fill the stomach of the son of Adam but dust."
And we used so recite a surah which resembled one of the surahs of Musabbihat, and I have forgotten it,but remember (this much) out of it:" Oh people who believe, why do you say that which you do not practise" and “that is recorded in your necks as a witness (against you) and you would be asked about it on the Day of Resurrection"` [ sahih muslim 1050 ]
Multiple Hadiths mentioning the same missing verse of the Qur’an
Abdullah ibn Abbas reported that Umar ibn Khattab sat on the pulpit of Allah's Messenger (ﷺ) and said: Verily Allah sent Muhammad (ﷺ) with truth and He sent down the Book upon him, and
the verse of stoning was included in what was sent down to him. We recited it, retained it in our memory and understood it.Allah's Messenger (ﷺ) awarded the punishment of stoning to death (to the married adulterer and adulteress) and, after him, we also awarded the punishment of stoning,
I am afraid that with the lapse of time, the people (may forget it) and may say: We do not find the punishment of stoning in the Book of Allah,and thus go astray by abandoning this duty
prescribed by Allah. Stoning is a duty laid down in Allah's Bookfor married men and women who commit adultery when proof is established, or it there is pregnancy, or a confession [ sahih muslim 1691a ]
It was narrated that Yahya said: I heard Saeed bin al-Musayyab (say) that Umar said: Beware of neglecting the verse of stoning, lest someone says,
We do not find two hadd punishments in the Book of Allah,for I saw the Prophet (ﷺ) stone [adulterers] and we stoned [adulterers] too [ musnad Ahmed 249 ]
Narrated Ibn Abbas: Umar said, "I am afraid that after a long time has passed, people may say, "
We do not find the Verses of the Rajam (stoning to death) in the Holy Book,"and consequently they may go astray by leaving an obligation that Allah has revealed. Lo! I confirm that the penalty of Rajam be inflicted on him who commits illegal sexual intercourse, if he is already married and the crime is proved by witnesses or pregnancy or confession." Sufyan added, "I have memorized this narration in this way." Umar added, "Surely Allah's Messenger (ﷺ) carried out the penalty of Rajam, and so did we after him." [ sahih bukhari 6829 ]
Disagreement between the Sahabah on the correct writing of a word in the Qur’an
...Zaid bin Thabit said: 'I missed an Ayah of Surat Al-Ahzab that I heard the Messenger of Allah (ﷺ) reciting: Among the believers are men who have been true to their covenant with Allah, of them some have fulfilled their obligations, and some of them are still waiting (33:23) - so I searched for it and found it with Khuzaimah bin Thabit, or Abu Khuzaimah, so I put it in its Surah.'" Az-Zuhri said:
"They differed then with At-Tabut and At-Tabuh. The Quraish said: At-Tabut while Zaid said: At-Tabuh. Their disagreement was brought to Uthman, so he said: 'Write it as At-Tabut, for it was revealed in the tongue of the Quraish.'"[ Jami At-Tirmidhi volume 5 book 44 hadith number 3104 ]
The omission of part of the recitation of one of Muhammad’s approved Qur’an reciters
Narrated Ibn Abbas: Umar said,
”Ubayy was the best of us in the recitation (of the Qur'an) yet we leave some of what he recites.”Ubayy says, “I have taken it from the mouth of Allah's Messenger (ﷺ) and will not leave for anything whatever." But Allah said "None of Our Revelations do We abrogate or cause to be forgotten but We substitute something better or similar." (2.106 ) [ sahih bukhari 5005 ]
The opposition of Muhammad’s approved Qur’an reciter to Zayd Ibn Thabit’s compilation
Abdullah bin Masud disliked Zaid bin Thabit copying the Musahif,and he said: 'O you Muslim people! I am removed from recording the transcription of the Mushaf and it is overseen by a man, by Allah, when I accepted Islam he was but in the loins of a disbelieving man' - meaning Zaid bin Thabit - and it was regarding this that
Abdullah bin Mas'ud said: 'O people of Al-'Iraq! Keep the Musahif that are with you, and conceal them.For indeed Allah said: And whoever conceals something, he shall come with what he concealed on the Day of Judgement (3:161). So meet Allah with the Musahif.'" Az-Zuhri said: "It was conveyed to me that some men amongst the most virtuous of the Companions of the Messenger of Allah (ﷺ) disliked that view of Ibn Mas'ud." [ jami at tirmidhi 5:44:3104 ]
And finally, Allah’s statement that he will replace forgotten verses of the Qur’an with better or similar verses
We do not abrogate a verse
or cause it to be forgotten except that We bring forth [one] better than it or similar to itDo you not know that Allah is over all things competent?
[ sahih international’s translation of Qur’an 2:106 ]
Is the Qur’an Perfectly Preserved?