How was the order of the Qur'an decided?

The order of the Qur'an was established during the time of Caliph Uthman ibn Affan due to concerns about discrepancies in its recitation among different communities. Hudhaifa bin Al-Yaman expressed his fears regarding these differences, saying to Uthman, O chief of the Believers! Save this nation before they differ about the Book (Quran) as Jews and the Christians did before. Sahih al-Bukhari 61:510 In response, Uthman directed Hafsa, the widow of the Prophet Muhammad ﷺ, to send the manuscripts of the Qur'an so that they could compile them into perfect copies.

Uthman then appointed a team of scribes, including Zaid bin Thabit, Abdullah bin Az-Zubair, Said bin Al-As, and Abdur-Rahman bin Harith bin Hisham, to undertake this task. Uthman instructed them to write the Qur'an in the dialect of Quraish, stating, "In case you disagree with Zaid bin Thabit on any point in the Qur'an, then write it in the dialect of Quraish, the Qur'an was revealed in their tongue." Once they had completed the copies, Uthman sent these standardized versions to various Muslim provinces and ordered that all other Qur'anic materials, whether incomplete or whole, be burnt to prevent any further discrepancies.

This process not only standardized the text but also ensured that the Qur'an was preserved in its authentic form, as it had been revealed. The compilation was carried out with meticulous care, reflecting the profound respect the early Muslim community held for the Qur'an as the word of God.