Sunan Abi Dawud, Hadith 2561

Abu Hurairah reported the Prophet as saying “Do not treat the backs of your beasts as pulpits, for Allaah has made them subject to you only to convey you to a town which you cannot reach without difficulty and He has appointed the earth (a floor to work) for you, so conduct your business on it.

حَدَّثَنَا عَبْدُ الْوَهَّابِ بْنُ نَجْدَةَ، حَدَّثَنَا ابْنُ عَيَّاشٍ، عَنْ يَحْيَى بْنِ أَبِي عَمْرٍو السَّيْبَانِيِّ، عَنِ ابْنِ أَبِي مَرْيَمَ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ إِيَّاكُمْ أَنْ تَتَّخِذُوا ظُهُورَ دَوَابِّكُمْ مَنَابِرَ فَإِنَّ اللَّهَ إِنَّمَا سَخَّرَهَا لَكُمْ لِتُبَلِّغَكُمْ إِلَى بَلَدٍ لَمْ تَكُونُوا بَالِغِيهِ إِلاَّ بِشِقِّ الأَنْفُسِ وَجَعَلَ لَكُمُ الأَرْضَ فَعَلَيْهَا فَاقْضُوا حَاجَتَكُمْ ‏" ‏ ‏.‏

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also referenced under: Hadith 2567 (DarusSalam)