Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
muslim:2032aAbū Bakr b. Abū Shaybah And Zuhayr b. Ḥarb And Muḥammad b. Ḥātim > Ibn Mahdī > Sufyān > Saʿd b. Ibrāhīm > Ibn Kaʿb b. Mālik from his father

Ibn Ka'b b. Malik reported on the authority of his father that he saw Messenger of Allah ﷺ licking his three fingers (after having finished the food). Ibn Hatim made no mention of" three". This hadith is also narrated through another chain of transmitters.  

مسلم:٢٠٣٢aحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ وَزُهَيْرُ بْنُ حَرْبٍ وَمُحَمَّدُ بْنُ حَاتِمٍ قَالُوا حَدَّثَنَا ابْنُ مَهْدِيٍّ عَنْ سُفْيَانَ عَنْ سَعْدِ بْنِ إِبْرَاهِيمَ عَنِ ابْنِ كَعْبِ بْنِ مَالِكٍ عَنْ أَبِيهِ قَالَ

رَأَيْتُ النَّبِيَّ ﷺ يَلْعَقُ أَصَابِعَهُ الثَّلاَثَ مِنَ الطَّعَامِ وَلَمْ يَذْكُرِ ابْنُ حَاتِمٍ الثَّلاَثَ وَقَالَ ابْنُ أَبِي شَيْبَةَ فِي رِوَايَتِهِ عَنْ عَبْدِ الرَّحْمَنِ بْنِ كَعْبٍ عَنْ أَبِيهِ