حَدَّثَنَا أَحْمَدُ بْنُ حَنْبَلٍ، حَدَّثَنَا بِشْرٌ، - يَعْنِي ابْنَ الْمُفَضَّلِ - عَنِ ابْنِ عَجْلاَنَ، عَنْ سَعِيدٍ الْمَقْبُرِيِّ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ إِذَا وَقَعَ الذُّبَابُ فِي إِنَاءِ أَحَدِكُمْ فَامْقُلُوهُ فَإِنَّ فِي أَحَدِ جَنَاحَيْهِ دَاءً وَفِي الآخَرِ شِفَاءً وَإِنَّهُ يَتَّقِي بِجَنَاحِهِ الَّذِي فِيهِ الدَّاءُ فَلْيَغْمِسْهُ كُلَّهُ ‏"‏ ‏.‏

Abu Hurairah reported the Messenger of Allah (PBUH) as saying: when a fly alights in anyone’s vessel, he should plunge it all in, for in one of its wings there is a disease, and in the other is a cure. It prevents the wing of it is which there is a cure, so plunge it all in (the vessel). Translation Not Available

Book Ref: Sunan Abi Dawud Book 28 Hadith 3844
Web Ref:  Sunan Abi Dawud Book 27 Hadith 3835