Rafi‘ b. Khadij said that one of the Ansar was killed at Khaibar and his relatives went to the Prophet (ﷺ) and mentioned that to him. He asked, “Have you two witnesses who can testify to the murderer of your friend?" They replied, “Messenger of God, there was not a single Muslim present, but only Jews who sometimes have the audacity to do even greater crimes than this “He said, “Then choose fifty of them and demand that they take an oath;" but they refused and God’s Messenger paid his blood wit himself. Abu Dawud transmitted it.

عَنْ رَافِعِ بْنِ خَدِيجٍ قَالَ: أَصْبَحَ رَجُلٌ مِنَ الْأَنْصَارِ مَقْتُولًا بِخَيْبَرَ فَانْطَلَقَ أَوْلِيَاؤُهُ إِلَى النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَذَكَرُوا ذَلِكَ لَهُ فَقَالَ: «أَلَكُمْ شَاهِدَانِ يَشْهَدَانِ عَلَى قَاتِلِ صَاحِبِكُمْ؟» قَالُوا: يَا رَسُولَ اللَّهِ لَمْ يَكُنْ ثَمَّ أحدٌ من المسلمينَ وإِنما هُوَ يهود وَقد يجترئون عَلَى أَعْظَمَ مِنْ هَذَا قَالَ: «فَاخْتَارُوا مِنْهُمْ خَمْسِينَ فَاسْتَحْلِفُوهُمْ» . فَأَبَوْا فَوَدَاهُ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِنْ عِنْدِهِ. رَوَاهُ أَبُو دَاوُد