This hadeeth comes under the following chapter: THE MERIT OF LICKING THE FINGERS AFTER TAKING FOOD AND WIPING THE DISH (WITH FINGERS) AND EATING OF THE FALLEN MOUTHFUL AFTER REMOVING THE DIRT STICKING TO IT
Ibn 'Abbas reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: When any one of you eats food he should not wipe his hand until he has licked it or got it licked by (someone else).