After the death of the Prophet, may Allah bless him and grant him peace, the task fell on this fortunate young man who specialized in the Quran to authenticate the first and most important reference for the ummah of Muhammad. This became an urgent task after the wars of apostasy and the Battle of Yamamah in particular in which a large number of those who had committed the Quran to memory perished.
Umar convinced the Khalifah Abu Bakr that unless the Quran was collected in one manuscript, a large part of it was in danger of being lost. Abu Bakr summoned Zayd ibn Thabit and said to him: "You are an intelligent young man and we do not suspect you (of telling lies or of forgetfulness) and you used to write the Divine revelation for Allah's Messenger. Therefore look for (all parts of) the Quran and collect it in one manuscript."
Zayd was immediately aware of the weighty responsibility. He later said: "By Allah, if he (Abu Bakr) had ordered me to shift one of the mountains from its place, it would not have been harder for me than what he had ordered me concerning the collection of the Quran."
Zayd finally accepted the task and, according to him, "started locating the Quranic material and collecting it from parchments, scapula, leafstalks of date palms and from the memories of men (who knew it by heart)".
 It was a painstaking task and Zayd was careful that not a single error, however slight or unintentional, should creep into the work. When Zayd had completed his task, he left the prepared suhuf or sheets with Abu Bakr. Before he died, Abu Bakr left the suhuf with Umar who in turn left it with his daughter Hafsah. Hafsah, Umm Salamah and Aishah were wives of the Prophet, may Allah be pleased with them, who memorized the Quran.
During the time of Uthman, by which time Islam had spread far and wide, differences in reading the Quran became obvious. A group of companions of the Prophet, headed by Hudhayfah ibn al-Yaman, who was then stationed in Iraq, came to Uthman and urged him to "save the Muslim ummah before they differ about the Quran".
Uthman obtained the manuscript of the Quran from Hafsah and again summoned the leading authority, Zayd ibn Thabit, and some other competent companions to make accurate copies of it. Zayd was put in charge of the operation. He completed the task with the same meticulousness with which he compiled the original suhuf during the time of Abu Bakr.
Zayd and his assistants wrote many copies. One of these Uthman sent to every Muslim province with the order that all other Quranic materials whether written in fragmentary manuscripts or whole copies be burnt. This was important in order to eliminate any variations or differences from the standard text of the Quran. Uthman kept a copy for himself and returned the original manuscript to Hafsah.
Zayd ibn Thabit thus became one of the foremost authorities on the Quran. Umar ibn al-Khattab once addressed the Muslims and said: "O people, whoever wants to ask about the Quran, let him go to Zayd ibn Thabit."
And so it was that seekers of knowledge from among the companions of the Prophet and the generation who succeeded them, known as the "Tabiun", came from far and wide to benefit from his knowledge. When Zayd died, Abu Hurayrah said: "Today, the scholar of this ummah has died."
When a Muslim holds the Quran and reads it or hears it being recited, surah after surah, ayah after ayah, he should know that he owes a tremendous debt of gratitude and recognition to a truly great companion of the Prophet, Zayd ibn Thabit, for helping to preserve for all time to come the Book of Eternal Wisdom. Truly did Allah, the Blessed and Exalted, say: "Surely We have revealed the Book of Remembrance and We shall certainly preserve it." (The Quran, Surah al-Hijr, 15:9)
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