"When anyone of you eats food, let him not wipe his hand until he licks it or has it licked." [Al-Bukhari]
عَنْ ابْنِ عَبَّاسٍ -ما- أَنَّ النَّبِيَّ -صلى الله عليه وسلم- قَالَ: ««إذَا أَكَلَ أَحَدُكُمْ طَعَامًا فَلا يَمْسَحْ يَدَهُ حَتَّى يَلْعَقَهَا، أَوْ يُلْعِقَهَا». (البخاري)