AHMAD 4322:
from Ibn Masʿūd —
[Machine] "Read to me, O Messenger of Allah, Surah Al-Ahqaf and I read it afterwards. Then, he differed with me regarding a verse from it, so I said, 'Who taught you how to recite?' He said, 'The Messenger of Allah taught me.' So, I said, 'The Messenger of Allah has taught me to recite it like this and that.' Therefore, I went to the Messenger of Allah while a man was with him and I said, 'O Messenger of Allah, did you not teach me to recite it like this and that?' He answered, 'Yes.' Then, the other man said, 'Did you not teach me to recite it like this and that?' He also answered, 'Yes.' Then, the face of the Messenger of Allah became red, and he said to the man who was with him, 'Both of you recite individually as you have heard it, for the people who were before you have been destroyed or ruined by their disagreements. Hence, I do not know whether I will order him (meaning the recitation) or do something that was already said before me.'"
أحمد ٤٣٢٢:
عن ابن مسعود —
أَقْرَأَنِي رَسُولُ اللهِ ﷺ سُورَةَ الْأَحْقَافِ وَأَقْرَأَهَا آخَرَ فَخَالَفَنِي فِي آيَةٍ مِنْهَا فَقُلْتُ مَنْ أَقْرَأَكَ؟ قَالَ أَقْرَأَنِي رَسُولُ اللهِ ﷺ فَقُلْتُ لَقَدْ أَقْرَأَنِي رَسُولُ اللهِ ﷺ كَذَا وَكَذَا فَأَتَيْتُ رَسُولَ اللهِ ﷺ وَعِنْدَهُ رَجُلٌ فَقُلْتُ يَا رَسُولَ اللهِ أَلَمْ تُقْرِئْنِي كَذَا وَكَذَا؟ قَالَ بَلَى قَالَ الْآخَرُ أَلَمْ تُقْرِئْنِي كَذَا وَكَذَا؟ قَالَ بَلَى فَتَمَعَّرَ وَجْهُ رَسُولِ اللهِ ﷺ فَقَالَ الرَّجُلُ الَّذِي عِنْدَهُ لِيَقْرَأْ كُلُّ وَاحِدٍ مِنْكُمَا كَمَا سَمِعَ فَإِنَّمَا هَلَكَ أَوْ أُهْلِكَ مَنْ كَانَ قَبْلَكُمْ بِالِاخْتِلَافِ فَمَا أَدْرِي أَأَمَرَهُ بِذَاكَ أَوْ شَيْءٍ قَالَهُ مِنْ قِبَلِهِ
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