Excellence of Eating with three Fingers and Licking them

Imam Al-Nawawi’s Riyad-us-Saliheen
Chapter 109
Excellence of Eating with three Fingers and Licking them

748. Ibn `Abbas (May Allah be pleased with them) reported: Messenger of Allah (sallallaahu ’alayhi wa sallam) 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].

749. Ka`b bin Malik (May Allah be pleased with him) reported: I saw Messenger of Allah (sallallaahu ’alayhi wa sallam) eating with three fingers (i.e., the thumb, the index finger and the middle finger) and licking them after having finished the food.
[Muslim].

750. Jabir (May Allah be pleased with him) reported: Messenger of Allah (sallallaahu ’alayhi wa sallam) commanded the licking of fingers and the gleaning of the dish, saying, “You do not know in which portion the blessing lies.”
[Muslim].

751. Jabir (May Allah be pleased with him) reported: Messenger of Allah (sallallaahu ’alayhi wa sallam) said, “When a morsel of any of you falls, he should pick it up and remove any of the dirt on it and then eat it, and should not leave it for Satan nor should wipe his hand with towel until he has licked his fingers, for he does not know in what portion of the food the blessing lies.”
[Muslim].

752. Jabir (May Allah be pleased with him) reported: Messenger of Allah (sallallaahu ’alayhi wa sallam) said, “Satan appears at every thing done by you; he appears even at one’s dinner. When a morsel of any of you falls, he should pick it up and remove any dirt on it, and then eat it. He should not leave it for Satan, nor should he wipe his hand with the towel until he has licked his fingers, for he does not know in what portion of the food the blessing lies.”
[Muslim].

753. Anas (May Allah be pleased with him) reported: Whenever Messenger of Allah (sallallaahu ’alayhi wa sallam) ate food, he would lick his three fingers and say, “If anyone of you drops a morsel of food, he should remove any dirt that may have stuck on it and then eat it, and should not leave it for Satan.” He (sallallaahu ’alayhi wa sallam) also commanded us that we should glean the pot, saying, “You do not know in which part of your food the blessings lies.”
[Muslim].

754. Sa`id bin Al-Harith reported: I asked Jabir (May Allah be pleased with him) whether it was obligatory to make Wudu’ for Salat (prayer) after eating cooked food. He said: “No, because in the lifetime of Messenger of Allah (sallallaahu ’alayhi wa sallam), such food was rarely available. We had no handkerchiefs, so when we ate such food we would wipe our fingers against our palms, forearms or (the sole of our) feet, and would offer Salat without fresh Wudu’ (for prayer).”
[Al-Bukhari].