Sunan Abi Dawud, Hadith 1659

Abu Sa’id al-Khudri said While we were traveling along with the Messenger of Allah a man came to him on his she camel, and began to drive her right and left. The Messenger of Allah said he who has a spare riding beast should give it to him who has no riding beast; and he who has surplus equipment should give it to who has no equipment. We thought that none of us had a right in surplus property.

حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الْخُزَاعِيُّ، وَمُوسَى بْنُ إِسْمَاعِيلَ، قَالاَ حَدَّثَنَا أَبُو الأَشْهَبِ، عَنْ أَبِي نَضْرَةَ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ، قَالَ بَيْنَمَا نَحْنُ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فِي سَفَرٍ إِذْ جَاءَ رَجُلٌ عَلَى نَاقَةٍ لَهُ فَجَعَلَ يَصْرِفُهَا يَمِينًا وَشِمَالاً فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنْ كَانَ عِنْدَهُ فَضْلُ ظَهْرٍ فَلْيَعُدْ بِهِ عَلَى مَنْ لاَ ظَهْرَ لَهُ وَمَنْ كَانَ عِنْدَهُ فَضْلُ زَادٍ فَلْيَعُدْ بِهِ عَلَى مَنْ لاَ زَادَ لَهُ ‏" ‏ ‏.‏ حَتَّى ظَنَنَّا أَنَّهُ لاَ حَقَّ لأَحَدٍ مِنَّا فِي الْفَضْلِ ‏.‏

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also referenced under: Hadith 1663 (DarusSalam)