Abu Hurayrah (may Allah be pleased with him) reports from the Prophet (peace and blessings be upon him): "Among the Children of Israel there was a succession of prophets: when one passed away, another came. But there will be no prophet after me; however, there will be many caliphs." They asked: "Then what do you command us?" He said: "Obey whichever of them comes first and give him his right; as for the rest, Allah will ask them about those placed in their care."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16548