Sahih Muslim Book 005, Hadith Number 2357.

Chapter : Blessing for him who presents Sadaqa.

Abu Huraira reported: Whenever the Apostle of Allah (may peace be upon him) was presented with food, he asked about it, If he was told that it was a gift, he ate out of that, and if he was told that it was a sadaqa he did not eat out of that.

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