I heard from Sayyiduna Abu Barzah Aslami (may Allah be pleased with him), who narrated from the Noble Prophet (peace and blessings be upon him): He (peace and blessings be upon him) said: The caliphs and rulers will be from among the Quraysh. When mercy is sought from them, they will show mercy; when they make a promise to anyone, they will fulfill it; and when they make judgments, they will do so with justice and fairness. If anyone among them does not fulfill these responsibilities, then upon him will be the curse of Allah, the angels, and all people.