Sahih al-Bukhari — Representation, Authorization, Business by Proxy — Hadith No: 2301
Translation
Narrated `Abdur-Rahman bin `Auf:I got an agreement written between me and Umaiya bin Khalaf that Umaiya would look after my property (or family) in Mecca and I would look after his in Medina. When I mentioned the word 'Ar-Rahman' in the documents, Umaiya said, "I do not know 'Ar-Rahman.' Write down to me your name, (with which you called yourself) in the Pre-Islamic Period of Ignorance." So, I wrote my name ' `Abdu `Amr'. On the day (of the battle) of Badr, when all the people went to sleep, I went up the hill to protect him. Bilal(1) saw him (i.e. Umaiya) and went to a gathering of Ansar and said, "(Here is) Umaiya bin Khalaf! Woe to me if he escapes!" So, a group of Ansar went out with Bilal to follow us (`Abdur-Rahman and Umaiya). Being afraid that they would catch us, I left Umaiya's son for them to keep them busy but the Ansar killed the son and insisted on following us. Umaiya was a fat man, and when they approached us, I told him to kneel down, and he knelt, and I laid myself on him to protect him, but the Ansar killed him by passing their swords underneath me, and one of them injured my foot with his sword. (The sub narrator said, " `Abdur-Rahman used to show us the trace of the wound on the back of his foot)