كتاب الأضاحى
35  
The Book of Sacrifices
(5)
Chapter: The prohibition of eating sacrificial meat for more than three days, which applied at the beginning of Islam but was then abrogated, and now it is permissible to eat it as long as one wants.
(5)
باب بَيَانِ مَا كَانَ مِنَ النَّهْىِ عَنْ أَكْلِ لُحُومِ الأَضَاحِيِّ بَعْدَ ثَلاَثٍ فِي أَوَّلِ الإِسْلاَمِ وَبَيَانِ نَسْخِهِ وَإِبَاحَتِهِ إِلَى مَتَى شَاءَ
Sahih Muslim 1969 b

Abu 'Ubaid, the freed slave of Ibn Azhar, reported that he said 'Id (prayer) with Umar b. al-Khattab, and then said the 'Id (prayer) with 'Ali b. Abu Talib. He (the narrator further) reported:

He led us in prayer before delivering the sermon and then addressed the people saying: Allah's Messenger (ﷺ) has forbidden you to eat the flesh of your sacrificial animals beyond three nights, so do not eat that.
حَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، أَخْبَرَنَا ابْنُ وَهْبٍ، حَدَّثَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، حَدَّثَنِي أَبُو عُبَيْدٍ، مَوْلَى ابْنِ أَزْهَرَ أَنَّهُ شَهِدَ الْعِيدَ مَعَ عُمَرَ بْنِ الْخَطَّابِ قَالَ ثُمَّ صَلَّيْتُ مَعَ عَلِيِّ بْنِ أَبِي طَالِبٍ - قَالَ - فَصَلَّى لَنَا قَبْلَ الْخُطْبَةِ ثُمَّ خَطَبَ النَّاسَ فَقَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَدْ نَهَاكُمْ أَنْ تَأْكُلُوا لُحُومَ نُسُكِكُمْ فَوْقَ ثَلاَثِ لَيَالٍ فَلاَ تَأْكُلُوا ‏.‏
Reference : Sahih Muslim 1969b
In-book reference : Book 35, Hadith 35
USC-MSA web (English) reference : Book 22, Hadith 4851
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