What did the commander of the Muslim army, Khalid bin Al-Walid (peace be upon him), do after the Muslims defeated the Byzantines, according to the narration of Ibn `Umar (peace be upon him)?
 Narrated Ibn `Umar:                     That he was riding a horse on the day, the Muslims fought (against the Byzantines), and the commander of the Muslim army was Khalid bin Al-Walid who had been appointed by Abu Bakr. The enemy took the horse away, and when the enemy was defeated, Khalid returned the horse to him.