It was said to the Prophet ﷺ "Would that you see ʿAbdullah bin Ubai." So, the Prophet ﷺ went to him, riding a donkey, and the Muslims accompanied him, walking on salty barren land. When the Prophet ﷺ reached ʿAbdullah bin Ubai, the latter said, "Keep away from me! By Allah, the bad smell of your donkey has harmed me." On that an Ansari man said (to ʿAbdullah), "By Allah! The smell of the donkey of Messenger of Allah ﷺ is better than your smell." On that a man from ʿAbdullah's tribe got angry for ʿAbdullah's sake, and the two men abused each other which caused the friends of the two men to get angry, and the two groups started fighting with sticks, shoes and hands. We were informed that the following Divine Verse was revealed (in this concern):-- "And if two groups of Believers fall to fighting then, make peace between them." (49.9)  

قِيلَ لِلنَّبِيِّ ﷺ لَوْ أَتَيْتَ عَبْدَ اللَّهِ بْنَ أُبَىٍّ فَانْطَلَقَ إِلَيْهِ النَّبِيُّ ﷺ وَرَكِبَ حِمَارًا فَانْطَلَقَ الْمُسْلِمُونَ يَمْشُونَ مَعَهُ وَهْىَ أَرْضٌ سَبِخَةٌ فَلَمَّا أَتَاهُ النَّبِيُّ ﷺ فَقَالَ إِلَيْكَ عَنِّي وَاللَّهِ لَقَدْ آذَانِي نَتْنُ حِمَارِكَ فَقَالَ رَجُلٌ مِنَ الأَنْصَارِ مِنْهُمْ وَاللَّهِ لَحِمَارُ رَسُولِ اللَّهِ ﷺ أَطْيَبُ رِيحًا مِنْكَ فَغَضِبَ لِعَبْدِ اللَّهِ رَجُلٌ مِنْ قَوْمِهِ فَشَتَمَا فَغَضِبَ لِكُلِّ وَاحِدٍ مِنْهُمَا أَصْحَابُهُ فَكَانَ بَيْنَهُمَا ضَرْبٌ بِالْجَرِيدِ وَالأَيْدِي وَالنِّعَالِ فَبَلَغَنَا أَنَّهَا أُنْزِلَتْ {وَإِنْ طَائِفَتَانِ مِنَ الْمُؤْمِنِينَ اقْتَتَلُوا فَأَصْلِحُوا بَيْنَهُمَا}  

Would that you approached Abdullah b. Ubayy (to persuade him to accept Islam). The Prophet ﷺ (accordingly) went to him, riding a donkey, and (a party of) Muslims also went (with him). On the way they had to walk over a piece of land affected with salinity. When the Prophet ﷺ approached him, he said: Do not come near me. By Allah, the obnoxious smell of your donkey has offended me. (As a rejoinder to this remark), a man from the Ansar said: By God, the smell of the donkey of the Messenger of Allah ﷺ is better than your smell. (At this), a man from the tribe of 'Abdullah got furious. Then people from both sides got furious and exchanged blows with sticks, hands and shoes. (The narrator says) that (after this scuffle) we learnt that (the Qur'anic verse):" It two parties of the Believers have a quarrel, make ye peace between them" (xlix. 9) was revealed about these fighting parties.  

قِيلَ لِلنَّبِيِّ ﷺ لَوْ أَتَيْتَ عَبْدَ اللَّهِ بْنَ أُبَىٍّ قَالَ فَانْطَلَقَ إِلَيْهِ وَرَكِبَ حِمَارًا وَانْطَلَقَ الْمُسْلِمُونَ وَهِيَ أَرْضٌ سَبِخَةٌ فَلَمَّا أَتَاهُ النَّبِيُّ ﷺ قَالَ إِلَيْكَ عَنِّي فَوَاللَّهِ لَقَدْ آذَانِي نَتْنُ حِمَارِكَ قَالَ فَقَالَ رَجُلٌ مِنَ الأَنْصَارِ وَاللَّهِ لَحِمَارُ رَسُولِ اللَّهِ ﷺ أَطْيَبُ رِيحًا مِنْكَ قَالَ فَغَضِبَ لِعَبْدِ اللَّهِ رَجُلٌ مِنْ قَوْمِهِ قَالَ فَغَضِبَ لِكُلِّ وَاحِدٍ مِنْهُمَا أَصْحَابُهُ قَالَ فَكَانَ بَيْنَهُمْ ضَرْبٌ بِالْجَرِيدِ وَبِالأَيْدِي وَبِالنِّعَالِ قَالَ فَبَلَغَنَا أَنَّهَا نَزَلَتْ فِيهِمْ { وَإِنْ طَائِفَتَانِ مِنَ الْمُؤْمِنِينَ اقْتَتَلُوا فَأَصْلِحُوا بَيْنَهُمَا}  

Would that you approached Abdullah b. Ubayy (to persuade him to accept Islam). The Prophet ﷺ (accordingly) went to him, riding a donkey, and (a party of) Muslims also went (with him). On the way they had to walk over a piece of land affected with salinity. When the Prophet ﷺ approached him, he said: Do not come near me. By Allah, the obnoxious smell of your donkey has offended me. (As a rejoinder to this remark), a man from the Ansar said: By God, the smell of the donkey of the Messenger of Allah ﷺ is better than your smell. (At this), a man from the tribe of 'Abdullah got furious. Then people from both sides got furious and exchanged blows with sticks, hands and shoes. (The narrator says) that (after this scuffle) we learnt that (the Qur'anic verse):" It two parties of the Believers have a quarrel, make ye peace between them" (xlix. 9) was revealed about these fighting parties. (Using translation from Muslim 1799)  

قِيلَ لِلنَّبِيِّ ﷺ لَوْ أَتَيْتَ عَبْدَ اللهِ بْنَ أُبَيٍّ فَانْطَلَقَ إِلَيْهِ نَبِيُّ اللهِ ﷺ وَرَكِبَ حِمَارًا وَانْطَلَقَ الْمُسْلِمُونَ يَمْشُونَ وَهِيَ أَرْضٌ سَبِخَةٌ فَلَمَّا أَتَاهُ النَّبِيُّ ﷺ قَالَ إِلَيْكَ عَنِّي فَوَاللهِلقَدْ آذَانِي رِيحُ حِمَارِكَ فَقَالَ رَجُلٌ مِنَ الْأَنْصَارِ وَاللهِ لَرِيحُ حِمَارِ رَسُولِ اللهِ ﷺ أَطْيَبُ رِيحًا مِنْكَ قَالَ فَغَضِبَ لِعَبْدِ اللهِ رَجُلٌ مِنْ قَوْمِهِ قَالَ فَغَضِبَ لِكُلِّ وَاحِدٍ مِنْهُمَا أَصْحَابُهُ قَالَ فَكَانَ بَيْنَهُمْ ضَرْبٌ بِالْجَرِيدِ وَبِالْأَيْدِي وَالنِّعَالِ قَالَ فَبَلَغَنَا أَنَّهَا نَزَلَتْ فِيهِمْ {وَإِنْ طَائِفَتَانِ مِنَ الْمُؤْمِنِينَ اقْتَتَلُوا فَأَصْلِحُوا بَيْنَهُمَا} [الحجرات 9]  

[Machine] It was said, "O Messenger of Allah, if you were to go to Abdullah bin Ubayy and speak to him, he would listen to you." So the Prophet ﷺ went to him and rode his donkey with some of his companions accompanying him. When he arrived, Abdullah said to him, "Step aside, for your donkey has disturbed me with its braying." A Muslim man said, "By Allah, the donkey of the Messenger of Allah ﷺ has a better fragrance than you." This angered both of them, and their respective groups started hitting each other with clods and sandals. It was then reported that this verse was revealed about them: "And if two factions among the believers should fight..." (Quran 49:9)  

قِيلَ يَا رَسُولَ اللهِ لَوْ أَتَيْتَ عَبْدَ اللهِ بْنَ أُبَيٍّ قَالَ فَانْطَلَقَ إِلَيْهِ وَرَكِبَ حِمَارَهُ وَرَكِبَ مَعَهُ قَوْمٌ مِنْ أَصْحَابِهِ فَلَمَّا أَتَاهُ قَالَ لَهُ عَبْدُ اللهِ تَنَحَّ فَقَدْ آذَانِي نَتْنُ حِمَارِكَ فَقَالَ رَجُلٌ مِنَ الْمُسْلِمِينَ وَاللهِ لَحِمَارُ رَسُولِ اللهِ ﷺ أَطْيَبُ رِيحًا مِنْكَ قَالَ فَغَضِبَ لِكُلِّ وَاحِدٍ مِنْهُمَا قَوْمُهُ فَتَضَارَبُوا بِالْجَرِيدِ وَالنِّعَالِ فَبَلَغَنَا إِنَّمَا نَزَلَتْ فِيهِمْ هَذِهِ الْآيَةُ {وَإِنْ طَائِفَتَانِ مِنَ الْمُؤْمِنِينَ اقْتَتَلُوا} [الحجرات 9] الْآيَةُ