Riyad as-Salihin, Book 3, Hadith 748 (In-Book)

Ibn 'Abbas (May Allah be pleased with them) reported: Messenger of Allah said, "When one of you finishes eating, he should not wipe his fingers until he has licked them himself or has given them to someone else to lick for him." [Al-Bukhari and Muslim].

عن ابن عباس رضى الله عنهما قال‏:‏ قال رسول الله صلى الله عليه وسلم‏:‏ ‏ "‏إذا أكل أحدكم طعاماً، فلا يمسح أصابعه حتى يلعقها أو يلعقها‏" ‏‏.‏ ‏‏ ‏.‏

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