“Rubai, the paternal aunt of Anas, broke the tooth of a girl and they (her family) asked (the girl's family) to let her off, but they refused. They offered to pay compensatory money, but they refused. So they came to Prophet ﷺ who ordered retaliation. Anas bin Nadr said: 'O Messenger of Allah ﷺ, will the tooth of Rubai' be broken? By the One Who sent you with the truth, it will not be broken!' The Prophet ﷺ said: 'O Anas, what Allah has decreed is retaliation.' So the people accepted that and forgave her. The Messenger of Allah ﷺ said: 'there are among the slaves of Allah those who, if they swear by Allah, Allah fulfills their oath.'” (Using translation from Ibn Mājah 2649)
أَنَّ الرُّبَيِّعَ عَمَّةَ أَنَسٍ كَسَرَتْ ثَنِيَّةَ جَارِيَةٍ فَطَلَبُوا إِلَى الْقَوْمِ الْعَفْوَ فَأَبَوْا فَأَتَوْا رَسُولَ اللهِ ﷺ فَقَالَ الْقِصَاصُ قَالَ أَنَسُ بْنُ النَّضْرِ يَا رَسُولَ اللهِ تَكْسِرُ ثَنِيَّةَ فُلَانَةَ فَقَالَ رَسُولُ اللهِ ﷺ يَا أَنَسُ كِتَابُ اللهِ الْقِصَاصُ قَالَ فَقَالَ وَالَّذِي بَعَثَكَ بِالْحَقِّ لَا تُكْسَرُ ثَنِيَّةُ فُلَانَةَ قَالَ فَرَضِيَ الْقَوْمُ فَعَفَوْا وَتَرَكُوا الْقِصَاصَ فَقَالَ رَسُولُ اللهِ ﷺ إِنَّ مِنْ عِبَادِ اللهِ مَنْ لَوْ أَقْسَمَ عَلَى اللهِ أَبَرَّهُ