I heard Hisham bin Hakim reciting Surat Al-Furqan during the lifetime of Allah's Messenger (ﷺ) and I listened to his recitation and noticed that he recited in several different ways which Allah's Messenger (ﷺ) had not taught me. I was about to jump over him during his prayer, but I controlled my temper, and when he had completed his prayer, I put his upper garment around his neck and seized him by it and said, "Who taught you this Surah which I heard you reciting?" He replied, "Allah's Messenger (ﷺ) taught it to me." I said, "You have told a lie, for Allah's Messenger (ﷺ) has taught it to me in a different way from yours." So I dragged him to Allah's Messenger (ﷺ) and said (to Allah's Messenger (ﷺ)), "I heard this person reciting Surah Al-Furqan in a way which you haven't taught me!" On that Allah's Apostle said, "Release him, (O `Umar!) Recite, O Hisham!" Then he recited in the same way as I heard him reciting. Then Allah's Messenger (ﷺ) said, "It was revealed in this way," and added, "Recite, O `Umar!" I recited it as he had taught me. Allah's Messenger (ﷺ) then said, "It was revealed in this way. This Qur'an has been revealed to be recited in 7 Ahruf (7 dialects / methods / many ways) , so recite of it whichever (way) is easier for you (or read as much of it as may be easy for you). [ Sahih]

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