Sahih al-Bukhari, Book 56, Hadith 278 (In-Book) ⓘ

Narrated Abu Huraira: Al-Hasan bin 'All took a date from the dates of the Sadaqa and put it in his mouth. The Prophet said (to him) in Persian, "Kakh, kakh! (i.e. Don't you know that we do not eat the Sadaqa (i.e. what is given in charity) (charity is the dirt of the people)).

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا غُنْدَرٌ، حَدَّثَنَا شُعْبَةُ، عَنْ مُحَمَّدِ بْنِ زِيَادٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه أَنَّ الْحَسَنَ بْنَ عَلِيٍّ، أَخَذَ تَمْرَةً مِنْ تَمْرِ الصَّدَقَةِ، فَجَعَلَهَا فِي فِيهِ، فَقَالَ النَّبِيُّ صلى الله عليه وسلم بِالْفَارِسِيَّةِ ‏ "‏ كَخٍ كَخٍ، أَمَا تَعْرِفُ أَنَّا لاَ نَأْكُلُ الصَّدَقَةَ ‏" ‏‏.‏