I heard Hisham b. Hakim (b. Hizam) reciting Surah al-Furqan in a different manner from my way of reciting, and the Messenger of Allah ﷺ had taught me to recite it. I nearly spoke sharply to him, but I delayed till he had finished. Then I caught his cloak at the neck, and I brought him to the Messenger of Allah ﷺ. I said: Messenger of Allah, I heard this man reciting Surah al-Furqan in a manner different from that in which you taught me to recite it. The Messenger of Allah ﷺ the told him to recite it. He then recited in the manner I heard him recite. The Messenger of Allah ﷺ said: Thus was it sent down. He then said to me: Recite, I recited (it). He then said: Thus was it sent down. He said: The Qur'an was sent down in seven modes of reading, so recite according to what comes most easily.  

سَمِعْتُ هِشَامَ بْنَ حَكِيمِ بْنِ حِزَامٍ يَقْرَأُ سُورَةَ الْفُرْقَانِ عَلَى غَيْرِ مَا أَقْرَؤُهَا وَكَانَ رَسُولُ اللَّهِ ﷺ أَقْرَأَنِيهَا فَكِدْتُ أَنْ أَعْجَلَ عَلَيْهِ ثُمَّ أَمْهَلْتُهُ حَتَّى انْصَرَفَ ثُمَّ لَبَّبْتُهُ بِرِدَائِهِ فَجِئْتُ بِهِ رَسُولَ اللَّهِ ﷺ فَقُلْتُ يَا رَسُولَ اللَّهِ إِنِّي سَمِعْتُ هَذَا يَقْرَأُ سُورَةَ الْفُرْقَانِ عَلَى غَيْرِ مَا أَقْرَأْتَنِيهَا فَقَالَ لَهُ رَسُولُ اللَّهِ ﷺ اقْرَأْ فَقَرَأَ الْقِرَاءَةَ الَّتِي سَمِعْتُهُ يَقْرَأُ فَقَالَ رَسُولُ اللَّهِ ﷺ هَكَذَا أُنْزِلَتْ ثُمَّ قَالَ لِي اقْرَأْ فَقَرَأْتُ فَقَالَ هَكَذَا أُنْزِلَتْ ثُمَّ قَالَ إِنَّ هَذَا الْقُرْآنَ أُنْزِلَ عَلَى سَبْعَةِ أَحْرُفٍ فَاقْرَءُوا مَا تَيَسَّرَ مِنْهُ  

These modes of reading aimed at the same point, not different in respect of lawful and unlawful.  

الزُّهْرِيُّ إِنَّمَا هَذِهِ الأَحْرُفُ فِي الأَمْرِ الْوَاحِدِ لَيْسَ تَخْتَلِفُ فِي حَلاَلٍ وَلاَ حَرَامٍ  

The Prophet ﷺ said: "Ubayy, I was asked to recite the Qur'an and I was asked: 'In one mode or two modes?' The angel that accompanied me said: 'Say, in two modes', I said: 'In two modes', I was asked again: 'In two or three modes'. The matter reached up to seven modes. He then said: 'Each mode is sufficiently health-giving, whether you utter 'all-hearing and all-knowing' or instead 'all-powerful and all-wise'. This is valid until you finish the verse indicating punishment on mercy and finish the verse indicating mercy on punishment."  

قَالَ النَّبِيُّ ﷺ يَا أُبَىُّ إِنِّي أُقْرِئْتُ الْقُرْآنَ فَقِيلَ لِي عَلَى حَرْفٍ أَوْ حَرْفَيْنِ فَقَالَ الْمَلَكُ الَّذِي مَعِي قُلْ عَلَى حَرْفَيْنِ قُلْتُ عَلَى حَرْفَيْنِ فَقِيلَ لِي عَلَى حَرْفَيْنِ أَوْ ثَلاَثَةٍ فَقَالَ الْمَلَكُ الَّذِي مَعِي قُلْ عَلَى ثَلاَثَةٍ قُلْتُ عَلَى ثَلاَثَةٍ حَتَّى بَلَغَ سَبْعَةَ أَحْرُفٍ ثُمَّ قَالَ لَيْسَ مِنْهَا إِلاَّ شَافٍ كَافٍ إِنْ قُلْتَ سَمِيعًا عَلِيمًا عَزِيزًا حَكِيمًا مَا لَمْ تَخْتِمْ آيَةَ عَذَابٍ بِرَحْمَةٍ أَوْ آيَةَ رَحْمَةٍ بِعَذَابٍ  

The Prophet ﷺ was present at the pool of Banu Ghifar, Gabriel came to him and said: "Allah has commanded you to make your community read (the Qur'an) in one harf. He (the Prophet) said: 'I beg Allah His pardon and forgiveness; my community has not strength to do so'. He then came for the second time and told him the same thing till he reached up to seven harfs. Finally, he said: 'Allah has commanded you to make your community read (the Qur'an) in seven harfs; in whichever mode they read, that will be correct.  

أَنَّ النَّبِيَّ ﷺ كَانَ عِنْدَ أَضَاةِ بَنِي غِفَارٍ فَأَتَاهُ جِبْرِيلُ ﷺ فَقَالَ إِنَّ اللَّهَ ﷻ يَأْمُرُكَ أَنْ تُقْرِئَ أُمَّتَكَ عَلَى حَرْفٍ قَالَ أَسْأَلُ اللَّهَ مُعَافَاتَهُ وَمَغْفِرَتَهُ إِنَّ أُمَّتِي لاَ تُطِيقُ ذَلِكَ ثُمَّ أَتَاهُ ثَانِيَةً فَذَكَرَ نَحْوَ هَذَا حَتَّى بَلَغَ سَبْعَةَ أَحْرُفٍ قَالَ إِنَّ اللَّهَ يَأْمُرُكَ أَنْ تُقْرِئَ أُمَّتَكَ عَلَى سَبْعَةِ أَحْرُفٍ فَأَيُّمَا حَرْفٍ قَرَءُوا عَلَيْهِ فَقَدْ أَصَابُوا