the Messenger or Allah approved of Qasamah as it had been during the Jahiliyyah. (Using translation from Nasāʾī 4707)   

عَنْ رَجُلٍ مِنْ أَصْحَابِ رَسُولِ اللهِ ﷺ مِنَ الْأَنْصَارِ أَنَّ رَسُولَ اللهِ ﷺ «أَقَرَّ الْقَسَامَةَ عَلَى مَا كَانَتْ عَلَيْهِ فِي الْجَاهِلِيَّةِ» وَاللَّفْظُ لِأَحْمَدَ  

Qasamah existed during the Jahiliyyah and the Messenger of Allah approved of it as it had been during the Jahiliyyah, and he ruled accordingly among some of the Ansar concerning a victim whom they claimed the Jews of Khaibar had Killed. (Sahih) Ma'mar contradicted the two of them. (Using translation from Nasāʾī 4708)  

عَنْ أُنَاسٍ مِنْ أَصْحَابِ رَسُولِ اللهِ ﷺ «أَنَّ الْقَسَامَةَ كَانَتْ فِي الْجَاهِلِيَّةِ فَأَقَرَّهَا رَسُولُ اللهِ ﷺ عَلَى مَا كَانَتْ عَلَيْهِ فِي الْجَاهِلِيَّةِ وَقَضَى بِهَا بَيْنَ نَاسٍ مِنَ الْأَنْصَارِ فِي قَتِيلٍ ادَّعَوْهُ عَلَى يَهُودِ خَيْبَرَ» قَالَ أَبُو عَبْدِ الرَّحْمَنِ خَالَفَهُمَا مَعْمَرٌ  

"Qasamah existed during the Jahiliyyah, then the Messenger of Allah confirmed it in the case of an Ansari who was found slain in the dry well of the jews, and Ansar said: "The Jews kill our companion."' (Using translation from Nasāʾī 4709)  

كَانَتِ الْقَسَامَةُ فِي الْجَاهِلِيَّةِ ثُمَّ أَقَرَّهَا رَسُولُ اللهِ ﷺ فِي الْأَنْصَارِيِّ الَّذِي وُجِدَ مَقْتُولًا فِي جُبِّ الْيَهُودِ فَقَالَتِ الْأَنْصَارُ «إِنَّ الْيَهُودَ قَتَلُوا صَاحِبَنَا»