Sahih Al Bukhari (681)

عن أنس (رضي الله عنه) قال "قيل للنبي (صلى الله عليه وسلم) لو أتيت عبد الله بن أبي فانطلق إليه النبي (صلى الله عليه وسلم) وركب حمارا فانطلق المسلمون يمشون معه وهي أرض سبخة فلما أتاه النبي (صلى الله عليه وسلم) فقال إليك عني والله لقد آذاني نتن حمارك فقال رجل من الأنصار منهم والله لحمار رسول الله (صلى الله عليه وسلم) أطيب ريحا منك فغضب لعبد الله رجل من قومه فشتمه فغضب لكل واحد منهما أصحابه فكان بينهما ضرب بالجريد والأيدي والنعال فبلغنا أنها أنزلت {وإن طائفتان من المؤمنين اقتتلوا فأصلحوا بينهما}".

Anas narrated: It was said to the Prophet (peace be upon him) "Would that you see `Abdullah ibn Ubay." So, the Prophet (peace be upon him) went to him, riding a donkey, and the Muslims accompanied him, walking on salty barren land. When the Prophet (peace be upon him) reached `Abdullah ibn Ubay, 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 `Abdullah): "By Allah! The smell of the donkey of Allah's Messenger (peace be upon him) is better than your smell." On that a man from `Abdullah's tribe got angry for `Abdullah'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."