One day some men of Bani Aws and Bani Khazraj were sitting together. The unity and brotherhood of the members of this group, who had been till a few days back the bloodthirsty enemies of one another, was very much disliked by a mischievous Jew who had joined them with a view to starting the evil plot of creating dissension and discord among the Muslims.
He reminded the men of Bani Aws and Bani Khazraj of the bitter memories of the past wars between the two tribes and narrated in detail the events of the Battle of Bu'ath, in which Bani Aws had eventually emerged victorious.
He dilated upon these old and long-forgotten events so much that strife and self glorification started between the two groups of Muslims (Aws and Khazraj). It was quite possible that a regular battle might have commenced but in the meantime the news reached the Prophet and he became aware of the nefarious plot of the Jews.
He, therefore, reached the spot with some of his companions and reminding the two groups of the aim of Islam and his own sublime programme said: "Islam has made you brothers of each other and has made all the enmities and the grudges a forgotten thing of the past". He counselled them for some time and reminded them of the result of their discord. Suddenly all of them began to cry and weep and embraced one another to strengthen their brotherhood and prayed to Allah for forgiveness.