Muwatta Malik, Book 54, Hadith 20 (USC-MSA)

Malik related to me from Ibn Shihab from Ubaydullah ibn Abdullah ibn Utba ibn Masud from Abdullah ibn Abbas from Maimuna, the wife of the Prophet, may Allah bless him and grant him peace, that the Messenger of Allah, may Allah bless him and grant him peace, was asked about a mouse falling into clarified butter. He said, "Remove it and throw away what is around it "

وَحَدَّثَنِي مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَبْدِ اللَّهِ بْنِ عُتْبَةَ بْنِ مَسْعُودٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَبَّاسٍ، عَنْ مَيْمُونَةَ، زَوْجِ النَّبِيِّ صلى الله عليه وسلم أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم سُئِلَ عَنِ الْفَأْرَةِ تَقَعُ فِي السَّمْنِ فَقَالَ ‏ "‏ انْزِعُوهَا وَمَا حَوْلَهَا فَاطْرَحُوهُ ‏" ‏ ‏.‏

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also referenced under: Book 54, Hadith 1785 (In-Book)