(18) باب اسْتِحْبَابِ لَعْقِ الأَصَابِعِ وَالْقَصْعَةِ وَأَكْلِ اللُّقْمَةِ السَّاقِطَةِ بَعْدَ مَسْحِ مَا يُصِيبُهَا مِنْ أَذًى وَكَرَاهَةِ مَسْحِ الْيَدِ قَبْلَ لَعْقِهَا
Jabir reported that Allah's Messenger (ﷺ) commanded the licking of fingers and the dish, saying:
You do not know in what portion the blessing lies." (ES)
Reference (ES): Sahih Muslim 2033 a (ES)
In-book reference (ES): Book 36, Hadith 174 (ES)
USC-MSA web (English) reference(deprecated numbering scheme): Book 23, Hadith 5043 (ES)