Jabir bin `Abdullah (may Allah be pleased with them) reported: the Messenger of Allah (may the peace and blessings of Allah be upon him) said:
Ward off oppression, as it will be darkness on the Day of Resurrection, and give up miserliness as it was a cause of perishing of those who lived before you; it drove them to shed each others'' blood and breach each others'' sanctity.

(Reported by Muslim)