Abu Huraira reported God’s messenger as saying, "When a fly alights in the vessel of any of you plunge it in, for in one of its wings there is disease and in the other a cure; it puts forward the one containing the disease, so dip it all in." Abu Dawud transmitted it.

وَعَنْ أَبِي هُرَيْرَةَ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا وَقَعَ الذُّبَابُ فِي إِنَاءِ أَحَدِكُمْ فَامْقُلُوهُ فَإِنَّ فِي أَحَدِ جَنَاحَيْهِ دَاءً وَفِي الْآخَرِ شِفَاءً فَإِنَّهُ يَتَّقِي بِجَنَاحِهِ الَّذِي فِيهِ الدَّاءُ فَلْيَغْمِسْهُ كُلَّهُ» . رَوَاهُ أَبُو دَاوُد