Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
suyuti:2-2457bIbrāhīm al-Taymī

[Machine] "Omar Ibn Al-Khattab isolated himself one day and began contemplating. He then sent a message to Ibn Abbas and said: How can this Ummah, its book is one, its prophet is one, and its Qiblah is one, differ? Ibn Abbas said: O Amir (leader)! Indeed, the Quran was revealed to us, so we recited it and learned the reasons for its revelation. However, after us, there will be people who will recite the Quran without knowing its reasons for revelation. Therefore, each group will have their own interpretation. If each group has their own interpretation and they differ, they will fight one another. Omar became enraged and scolded him, and Ibn Abbas left. Later, he called him again and acknowledged what he had said, then he said: Yes, you are right."  

السيوطي:٢-٢٤٥٧b

"خلا عُمَرُ بْنُ الْخَطَّابِ ذَاتَ يَوْمٍ فَجَعَلَ يُحَدِّثُ نَفْسَهُ، فَأَرْسَلَ إِلَى ابْنِ عَبَّاسٍ فَقَالَ: كَيْفَ تَخْتَلِفُ هَذِهِ الأُمَّةُ وكِتَابُهَا وَاحِدٌ، وَنَبِيُّهَا وَاحِدٌ وَقبْلَتُهَا وَاحِدَةٌ؟ قَالَ ابْنُ عَبَّاسٍ: يَا أَمِيرَ! إِنَّا أُنزِلَ عَلَيْنَا الْقُرْآنُ، فَقَرَأْنَاهُ وَعَلِمْنَا فِيمَا نَزَلَ، وَإِنَّهُ يَكُونُ بَعْدَنَا أقْوَامٌ يَقْرَأونَ الْقُرْآنَ لَا يَعْرِفُونَ فيمَ نَزَلَ، فَيَكُونُ لِكُلِّ قَوْمٍ فِيهِ رَأىٌ، فَإِنْ كَانَ لِكُلِّ قَوْمِ فِيهِ رَأىٌّ اخْتَلَفُوا (فَإذَا اخْتَلَفُوا) اقْتَتَلُوا، فَزَبَرَهُ عُمَر وَانْتَهَرَهُ، وَانْصَرَفَ ابنُ عَبَّاسٍ، ثُمَّ دَعَاهُ بَعْدُ فَعَرَفَ الَّذِى قَالَ، ثُمَّ قَالَ: إِيهًا أَعِدْ".  

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