1042 – ʿImrān ibn Ḥuṣayn (may Allah be pleased with him) said: “Yaʿlā ibn Umayya fought with a man. One of them bit the other, so the bitten man pulled his hand out of the biter’s mouth and, in doing so, knocked out one of his upper incisors. They took their case to the Prophet ﷺ, who said, ‘Would one of you bite his brother the way a stud (fahl) bites? No blood money is due for him.’ ” Agreed upon; the wording is that of Muslim (1).

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Glossary of the ḥadith
– Thanīyah: one of the four incisors at the front of the mouth—two upper and two lower.
– Fahl: the male of an animal (plural: fuhūl); here it refers to a male camel, the stud of the herd.

Points derived from the ḥadith
1 – Yaʿlā ibn Umayya had a dispute with an employee of his and bit the man’s hand. The victim wrenched his hand free, dislodging Yaʿlā’s incisor. When they brought the matter to the Prophet ﷺ, he ruled that no blood money was payable for the lost incisor and imposed no liability on either party. This view is held by the other three imams, whereas Imam Mālik requires compensation.
2 – The Prophet ﷺ reprimanded such conduct, saying: “Would one of you bite his brother the way a stud camel bites?!”
3 – The ḥadith establishes that the biter is the aggressor and that the person bitten has the right to defend himself. No compensation is due for damage that results from his lawful self-defense, because an authorized action incurs no liability for its consequences.