Sayyiduna Umar bin Khattab (may Allah be pleased with him) narrates: I heard Hisham bin Hakim reciting Surah Furqan in a way different from the way I recite it. The Prophet Muhammad (peace and blessings be upon him) himself taught me this Surah. At first, I was about to attack him, but then I waited. When he completed the prayer, I grabbed him by his cloak and took him to the Prophet Muhammad (peace and blessings be upon him). I said: I have heard this person reciting Surah Furqan in a manner different from the way you taught me to recite it. The Prophet Muhammad (peace and blessings be upon him) said to him: Recite. He recited in the same way as I had heard him. The Prophet Muhammad (peace and blessings be upon him) said: This verse was revealed in this way. Then he said to me: Recite. I recited, and he said: It was revealed in this way. Indeed, this Qur'an was revealed upon seven modes, so recite in whichever of them is easy for you.
Hadith Referenceصحیح ابن حبان / كتاب الرقائق / 741
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «صحيح أبي داود» (1325): ق.فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح على شرط الشيخين.