Ar-Rubai (the paternal aunt of Anas bin Malik) broke the incisor tooth of young Ansari girl. Her
family demanded the Qisas and they came to the Prophet (ﷺ) who passed the judgment of Qisas. Anas bin
An-Nadr (the paternal uncle of Anas bin Malik) said, "O Allah's Messenger (ﷺ)! By Allah, her tooth will not
be broken." The Prophet (ﷺ) said, "O Anas! (The law prescribed in) Allah's Book is Qisas." But the
people (i.e. the relatives of the girl) gave up their claim and accepted a compensation. On that Allah's
Apostle said, "Some of Allah's worshippers are such that if they take an oath, Allah will fulfill it for
them."
Sahih al-Bukhari Book 65, Hadith 133