Sharḥ ʿUmdatul Aḥkām
Kitāb al-Aṭʿimah – The Book of Eating
Translated Abu Ubaydah
Translated, Checked & Additional Notes
Abu Hibban & Abu Khuzaimah Ansaari
To Lick and Suck the Fingers After Eating
 Narrated Ibn `Abbas (Radi Allahu Anhu):
The Prophet (Sallalahu Alayhi Wa Sallam) said, ‘When you eat, do not wipe your hands till you have licked it, or had it licked by somebody else.”
[GRADING] – [BUKHARI]
Bukhari, Book of Food, Chapter: To lick and suck the fingers [no.5456]
Muslim, Book of Drinks, Chapter: It is recommended to lick one’s fingers and wipe the bowl [no.2031]
[RULINGS FROM THE HADITH]
1) The reason behind licking the fingers after eating is to ensure you don’t lose out from the blessings in the food. Nobody knows which part of their food contains the most blessings. This is why we have been commanded to lick the fingers (and finish the plate of food). This is from a hadith as transmitted in Muslim [no.2033] and Tirmidhi [no.1801]
2) Finishing the food on the plate and licking the fingers is a sign and way of honoring, dignifying and appreciating the food because it is a blessing from Allah. The food shouldn’t be thrown in the rubbish or sewers.
3) You should fill your plate to as much as is required so the plate can be finished.
4) Some ahadith mention the Messenger of Allah (Sallalahu Alayhi Wasallam) licked his three fingers (Thumb, Index and middle finger) [Muslim [no.2033] as narrated from a number of companions.
5) Your wife or child can be asked to lick your fingers.