Silsilat al-Ahadith al-Sahihah

Saeed bin Khalid says: I went to Abu Salamah, and he presented something made of butter, dates, and flour, etc. Meanwhile, a fly fell into the food. Abu Salamah dipped it (the fly) into the food with his finger. I said: Uncle! What are you doing? He said: Sayyiduna Abu Saeed Khudri (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, in one wing of the fly there is poison and in the other there is cure. If it falls into the food, then dip it completely, for it puts forward the wing with the poison and keeps back the wing with the cure."