The Messenger of Allah ﷺ said, "When a morsel of food falls from one of you, let him pick it up, remove whatever dirt is on it, and eat it. He should not leave it for Satan. And he should not wipe his hand with a cloth until he has licked his fingers, for he does not know in which part of his food the blessing lies."
قال رسول الله ﷺ: إذا وقعت لقمة أحدكم فليأخذها، فليمط ما كان بها من أذى وليأكلها، ولا يدعها للشيطان، ولا يمسح يده بالمنديل حتى يلعق أصابعه، فإنه لا يدري في أي طعامه البركة.
Muslim narrated it in the Book of Drinks (2033:134), from Muhammad bin Abdullah bin Numayr, who said, "My father narrated to us, Sufyan narrated to us, from Abu Zubayr, from Jabir," and he related it.