وَعَنْ أَبِي هُرَيْرَةَ رضى الله عنه
قَالَ: قَالَ رَسُولُ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ -«إِذَا وَقَعَ اَلذُّبَابُ فِي شَرَابِ أَحَدِكُمْ فَلْيَغْمِسْهُ، ثُمَّ لِيَنْزِعْهُ، فَإِنَّ فِي أَحَدِ جَنَاحَيْهِ دَاءً، وَفِي اَلْآخَرِ شِفَاءً»
Narrated Abu Hurayrah (rad): The Messenger of Allah (sallallahu alayhi wa sallam) said: “When a fly falls in the drink of one of you, he should fully dip it and then throw it away because there is disease in one of its wings and cure in the other”.
Bulugh al-Maram 17, Book 1, The Book of Purification, Hadith 17. 1 min read