The Book of Drinks (Kitab Al-Ashriba)

Muslim :: Book 23 : Hadith 5046

Jabir reported: I heard Allah's Apostle (may peace be upon him) as saying: The Satan is present with any one of you in everything he does; he is present even when he eats food; so if any one of you drops a mouthful he should remove away anything filthy on it and eat it and not leave for the devil; and when he finishes (food) he should lick his fingers, for he does not know in what portion of his food the blessing lies.

Source materials are from the University of Southern California MSA site
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