Narrated Abdullah Ibn Abbas: Qurayzah and Nadir (were two Jewish tribes). An-Nadir were nobler than Qurayzah. When a man of Qurayzah killed a man of an-Nadir, he would be killed. But if a man of an-Nadir killed a man of Qurayzah, a hundred wasq of dates would be paid as blood-money. When Prophethood was bestowed upon the Prophet صلی اللہ علیہ وسلم, a man of an-Nadir killed a man of Qurayzah. They said: Give him to us, we shall kill him. They replied: We have the Prophet صلی اللہ علیہ وسلم between you and us. So they came to him. Thereupon the following verse was revealed: If thou judge, judge in equity between them. In equity means life for a life. The following verse was then revealed: Do they seek of a judgment of (the days) ignorance? Abu Dawud said: Quraizah and al-Nadir were the descendants of Harun the Prophet صلی اللہ علیہ وسلم