Hadith 28:112
Sahih (Al-Albani)
Ibn ‘Abbas reported the Messenger of Allah (ﷺ) as saying :
When one of you eats, he must not wipe his hand with a handkerchief till he licks it or gives it to someone to lick.
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى، عَنِ ابْنِ جُرَيْجٍ، عَنْ عَطَاءٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِذَا أَكَلَ أَحَدُكُمْ فَلاَ يَمْسَحَنَّ يَدَهُ بِالْمِنْدِيلِ حَتَّى يَلْعَقَهَا أَوْ يُلْعِقَهَا "
Original Reference: Sunan Abi Dawud 3847