The Book of Zakat
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنْ مَنْصُورٍ، عَنْ طَلْحَةَ بْنِ مُصَرِّفٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم وَجَدَ تَمْرَةً فَقَالَ " لَوْلاَ أَنْ تَكُونَ مِنَ الصَّدَقَةِ لأَكَلْتُهَا " .Anas b. Malik reported that the Messenger of Allah (ﷺ) found a date in the street and said:If it were not of sadaqa I would have eaten it
From Sahih Muslim, whose reports the scholars accept as authentic.