"There were (the two tribes of) Quraizah and An-Nadir, and An-Nadir was nobler than Quraiaah. If a man of Quraizah Killed a man of An-Nadir, he would be killed in return, but if a man of An-Nadir killed a man of Quraizah, he would pay a Diyah of one hundred Wasqs of dates. When An-Nadir killed a man of Quraizah, and they said: 'Hand him over to us and we will kill him.' They said: 'Between us and you (as judge) is the Prophet.' So they came to him, then the following was revealed: "And if you judge, judge with justice between them."[3] Al-Qisl (justice) means a soul for a soul. Then the following was revealed: "Do they then seek the judgment of (the days of) Ignorance?"[4]  

كَانَ قُرَيْظَةُ وَالنَّضِيرُ وَكَانَ النَّضِيرُ أَشْرَفَ مِنْ قُرَيْظَةَ وَكَانَ إِذَا قَتَلَ رَجُلٌ مِنْ قُرَيْظَةَ رَجُلاً مِنَ النَّضِيرِ قُتِلَ بِهِ وَإِذَا قَتَلَ رَجُلٌ مِنَ النَّضِيرِ رَجُلاً مِنْ قُرَيْظَةَ أَدَّى مِائَةَ وَسْقٍ مِنْ تَمْرٍ فَلَمَّا بُعِثَ النَّبِيُّ ﷺ قَتَلَ رَجُلٌ مِنَ النَّضِيرِ رَجُلاً مِنْ قُرَيْظَةَ فَقَالُوا ادْفَعُوهُ إِلَيْنَا نَقْتُلْهُ فَقَالُوا بَيْنَنَا وَبَيْنَكُمُ النَّبِيُّ ﷺ فَأَتَوْهُ فَنَزَلَتْ { وَإِنْ حَكَمْتَ فَاحْكُمْ بَيْنَهُمْ بِالْقِسْطِ } وَالْقِسْطُ النَّفْسُ بِالنَّفْسِ ثُمَّ نَزَلَتْ { أَفَحُكْمَ الْجَاهِلِيَّةِ يَبْغُونَ }  

"Either judge between them, or turn away from them. If you turn away from then up to: those who act justly."[1] - were revealed concerning the matter of blood money between An-Nadir and Quraizah. That was because the slain of An-Nadir were of noble status, so the blood money would be paid in full for them, but for Banu Quraizah only half of the blood money would be paid. They referred the matter to the Messenger of Allah for judgment, then Allah, the Mighty and Sublime, revealed that concerning them, so the Messenger of Allah told them to do the right thing and he made the blood money equal.  

أَنَّ الآيَاتِ الَّتِي فِي الْمَائِدَةِ الَّتِي قَالَهَا اللَّهُ ﷻ { فَاحْكُمْ بَيْنَهُمْ أَوْ أَعْرِضْ عَنْهُمْ } إِلَى { الْمُقْسِطِينَ } إِنَّمَا نَزَلَتْ فِي الدِّيَةِ بَيْنَ النَّضِيرِ وَبَيْنَ قُرَيْظَةَ وَذَلِكَ أَنَّ قَتْلَى النَّضِيرِ كَانَ لَهُمْ شَرَفٌ يُودَوْنَ الدِّيَةَ كَامِلَةً وَأَنَّ بَنِي قُرَيْظَةَ كَانُوا يُودَوْنَ نِصْفَ الدِّيَةِ فَتَحَاكَمُوا فِي ذَلِكَ إِلَى رَسُولِ اللَّهِ ﷺ فَأَنْزَلَ اللَّهُ ﷻ ذَلِكَ فِيهِمْ فَحَمَلَهُمْ رَسُولُ اللَّهِ ﷺ عَلَى الْحَقِّ فِي ذَلِكَ فَجَعَلَ الدِّيَةَ سَوَاءً