Sahih al-Bukhari 2265, 2266
Narrated Ya`la bin Umaiya:
I fought in Jaish-al-Usra (Ghazwa of Tabuk) along with the Prophet (ﷺ) and in my opinion that was the 
best of my deeds. Then I had an employee, who quarrel led with someone and one of the them bit and 
cut the other's finger and caused his own tooth to fall out. He then went to the Prophet (with a 
complaint) but the Prophet (ﷺ) canceled the suit and said to the complainant, "Did you expect him to let 
his finger in your mouth so that you might snap and cut it (as does a stallion camel)?" 
Narrated Ibn Juraij from `Abdullah bin Abu Mulaika from his grandfather a similar story: A man bit 
the hand of another man and caused his own tooth to fall out, but Abu Bakr judged that he had no 
right for compensation (for the broken tooth).
حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا إِسْمَاعِيلُ ابْنُ عُلَيَّةَ، أَخْبَرَنَا ابْنُ جُرَيْجٍ، قَالَ أَخْبَرَنِي عَطَاءٌ، عَنْ صَفْوَانَ بْنِ يَعْلَى، عَنْ يَعْلَى بْنِ أُمَيَّةَ ـ رضى الله عنه ـ قَالَ غَزَوْتُ مَعَ النَّبِيِّ صلى الله عليه وسلم جَيْشَ الْعُسْرَةِ فَكَانَ مِنْ أَوْثَقِ أَعْمَالِي فِي نَفْسِي، فَكَانَ لِي أَجِيرٌ، فَقَاتَلَ إِنْسَانًا، فَعَضَّ أَحَدُهُمَا إِصْبَعَ صَاحِبِهِ، فَانْتَزَعَ إِصْبَعَهُ، فَأَنْدَرَ ثَنِيَّتَهُ فَسَقَطَتْ، فَانْطَلَقَ إِلَى النَّبِيِّ صلى الله عليه وسلم فَأَهْدَرَ ثَنِيَّتَهُ وَقَالَ ‏
"‏ أَفَيَدَعُ إِصْبَعَهُ فِي فِيكَ تَقْضَمُهَا ـ قَالَ أَحْسِبُهُ قَالَ ـ كَمَا يَقْضَمُ الْفَحْلُ ‏"‏‏.‏ قَالَ ابْنُ جُرَيْجٍ وَحَدَّثَنِي عَبْدُ اللَّهِ بْنُ أَبِي مُلَيْكَةَ، عَنْ جَدِّهِ، بِمِثْلِ هَذِهِ الصِّفَةِ أَنَّ رَجُلاً، عَضَّ يَدَ رَجُلٍ، فَأَنْدَرَ ثَنِيَّتَهُ، فَأَهْدَرَهَا أَبُو بَكْرٍ رضى الله عنه‏.‏