وَعَنْهُ قَالَ: «لَمَّا كَانَ يَوْمُ خَيْبَرَ، أَمَرَ رَسُولُ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَبَا طَلْحَةَ، فَنَادَى: «إِنَّ اَللَّهَ وَرَسُولَهُ يَنْهَيَانِكُمْ عَنْ لُحُومِ اَلْحُمُرِ]اَلْأَهْلِيَّةِ], فَإِنَّهَا رِجْسٌ»
On the day of Khaibair, the Messenger of Allah (sallallahu alayhi wa sallam) commanded Abu Talha to announce: “Allah and His Messenger have prohibited for you (eating of) the flesh of the donkeys, for it is unclean”.
Bulugh al-Maram 29, Book 1, The Book of Purification, Hadith 29. 1 min read