Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: The Prophet Muhammad (peace and blessings be upon him) said: "Among the Children of Israel, prophets used to succeed one another; whenever a prophet passed away, another prophet would come after him. But there will be no prophet after me." A man asked: "O Messenger of Allah (peace be upon him)! What will happen after you?" The Prophet (peace be upon him) said: "There will be caliphs, and there will be many (claimants to the caliphate)." The man asked: "O Messenger of Allah (peace be upon him)! What do you command us to do in that situation?" The Prophet (peace be upon him) said: "Fulfill the pledge of allegiance to the one to whom the pledge was first given; give them their due right, and for your right, Allah the Exalted will call them to account."
Hadith Referenceصحیح ابن حبان / كتاب السير / 4555
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «الإرواء» (8/ 127).فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح