Muwatta Malik, Book 20, Hadith 82 (USC-MSA)

Yahya related to me from Malik, from Ibn Shihab, that Salim ibn Abdullah heard Abu Hurayra relating to Abdullah ibn Umar how a group of three people in ihram had passed him at ar-Rabadha and had asked him for a fatwa about eating game which people who were not in ihram were eating, and he told them that they could eat it. He said, "Then I went to Umar ibn al-Khattab in Madina and asked him about it, and he said, 'What did you say to them?' and I said, 'I told them that they could eat it.' Umar said, 'If you had told them anything else I would have done you an injury.' "

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، أَنَّهُ سَمِعَ أَبَا هُرَيْرَةَ، يُحَدِّثُ عَبْدَ اللَّهِ بْنَ عُمَرَ أَنَّهُ مَرَّ بِهِ قَوْمٌ مُحْرِمُونَ بِالرَّبَذَةِ فَاسْتَفْتَوْهُ فِي لَحْمِ صَيْدٍ وَجَدُوا نَاسًا أَحِلَّةً يَأْكُلُونَهُ فَأَفْتَاهُمْ بِأَكْلِهِ قَالَ ثُمَّ قَدِمْتُ الْمَدِينَةَ عَلَى عُمَرَ بْنِ الْخَطَّابِ فَسَأَلْتُهُ عَنْ ذَلِكَ فَقَالَ بِمَ أَفْتَيْتَهُمْ قَالَ فَقُلْتُ أَفْتَيْتُهُمْ بِأَكْلِهِ ‏.‏ قَالَ فَقَالَ عُمَرُ لَوْ أَفْتَيْتَهُمْ بِغَيْرِ ذَلِكَ لأَوْجَعْتُكَ ‏.‏

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also referenced under: Book 20, Hadith 786 (In-Book)