Sahih Muslim Book 31, Hadith Number 6173.
Chapter : Instructions of Allah’s Apostle (may peace be upon him) in regard to the people of Egypt.
Abu Dharr reported Allah’s Messenger (may peace be upon him) as saying: You would soon conquer a land where people are in the habit of using foul language. They have a right of kinship upon you. And when you see two persons fighting for the space of a brick, then get out of that. He (Abu Dharr) then happened to pass by Rabila and ‘Abd al-Rahman, the two sons of Shurahbil b. Hasana, and they had been disputing for the space of a brick. So he left the land.