Abu Huraira said that when God’s messenger was brought food he asked whether it was a present or sadaqa, and if he was informed that it was sadaqa he told his companions to eat, but did not eat himself; if however he was informed that it was a present he put in his hand and ate along with them. (Bukhari and Muslim.)
Hadith Referenceمشكوة المصابيح / كتاب الزكاة / 1824
Hadith Gradingالألبانی:مُتَّفَقٌ عَلَيْهِ | زبیر علی زئی:متفق عليه
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «متفق عليه، رواه البخاري (2576) و مسلم (1077/175)»