It is narrated by Abu Nadr that he learnt from a letter sent by a man from the Aslam tribe, who was a Companion of the Holy Prophet ﷺ and whose name was Abdullah bin Abu Aufa, to Umar bin Ubaidullah when the latter marched upon Haruriyya (Khawarij) informing him that the Messenger of Allah ﷺ in one of those days when he was confronting the enemy waited until the sun had declined. Then he stood up (to address the people) and said: O ye men, do not wish for an encounter with the enemy. Pray to Allah to grant you security; (but) when you have to encounter them exercise patience, and you should know that Paradise is under the shadows of the swords. Then the Messenger of Allah ﷺ stood up (again) and said: O Allah. Revealer of the Book, Disperser of the clouds, Defeater of the hordes, put our enemy to rout and help us against them.