Section 1 Mishkat al-Masabih 4165
Arabic hadith text
وَعَنْ جَابِرٌ: أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَمَرَ بِلَعْقِ الْأَصَابِعِ وَالصَّفْحَةِ وَقَالَ:" إِنَّكُمْ لَا تَدْرُونَ: فِي أَيَّهِ الْبَرَكَةُ؟ ". رَوَاهُ مُسْلِمٌ
Translation
Jabir said the Prophet ordered people to lick their fingers and the dish, saying, “You do not know in what portion blessing lies.” Muslim transmitted it.