It is narrated from Hazrat Abu Barzah Aslami (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: The rulers will be from among the Quraysh; when mercy is requested from them, they will show mercy; when they make a promise, they will fulfill it; and when they judge, they will judge with justice. And whoever does not do so, upon him is the curse of Allah, the angels, and all mankind.