Sahih al-Bukhari 6920 (Book 93, Hadith 53)

Narrated Zaid bin Thabit: Abu Bakr sent for me owing to the large number of casualties in the battle of Al-Yamama, while
`Umar was sitting with him. Abu Bakr said (to me), `Umar has come to my and said, ‘A great number
of Qaris of the Holy Qur’an were killed on the day of the battle of Al-Yamama, and I am afraid that
the casualties among the Qaris of the Qur’an may increase on other battle-fields whereby a large part
of the Qur’an may be lost. Therefore I consider it advisable that you (Abu Bakr) should have the
Qur’an collected.’ I said, ‘How dare I do something which Allah’s Messenger (ﷺ) did not do?’ `Umar said, By
Allah, it is something beneficial.’ `Umar kept on pressing me for that till Allah opened my chest for
that for which He had opened the chest of `Umar and I had in that matter, the same opinion as `Umar
had.” Abu Bakr then said to me (Zaid), “You are a wise young man and we do not have any suspicion
about you, and you used to write the Divine Inspiration for Allah’s Messenger (ﷺ). So you should search for
the fragmentary scripts of the Qur’an and collect it (in one Book).” Zaid further said: By Allah, if Abu
Bakr had ordered me to shift a mountain among the mountains from one place to another it would not
have been heavier for me than this ordering me to collect the Qur’an. Then I said (to `Umar and Abu
Bakr), “How can you do something which Allah’s Messenger (ﷺ) did not do?” Abu Bakr said, “By Allah, it is
something beneficial.” Zaid added: So he (Abu Bakr) kept on pressing me for that until Allah opened
my chest for that for which He had opened the chests of Abu Bakr and `Umar, and I had in that
matter, the same opinion as theirs.
So I started compiling the Qur’an by collecting it from the leafless stalks of the date-palm tree and
from the pieces of leather and hides and from the stones, and from the chests of men (who had
memorized the Qur’an). I found the last verses of Sirat-at-Tauba: (“Verily there has come unto you an
Apostle (Muhammad) from amongst yourselves–‘ (9.128-129) ) from Khuza`ima or Abi Khuza`ima
and I added to it the rest of the Sura. The manuscripts of the Qur’an remained with Abu Bakr till Allah
took him unto Him. Then it remained with `Umar till Allah took him unto Him, and then with Hafsa
bint `Umar.