عَنِ النَّبِيّ صَلَّى اللّٰهُ عَلَيْهِ وَسَلَّم قَالَ: كَانَتْ بَنُو إِسْرَائِيلَ تَسُوسُهُمُ الأَنْبِيَاءُ، كُلَّمَا هَلَكَ نَبِيٌّ خَلَفَهُ نَبِيٌّ، وَإِنَّهُ لاَ نَبِيَّ بَعْدِي، وَسَيَكُونُ خُلَفَاءُ فَيَكْثُرُونَ. قَالُوا فَمَا تَأْمُرُنَا قَالَ فُوا بِبَيْعَةِ الأَوَّلِ فَالأَوَّلِ، أَعْطُوهُمْ حَقَّهُمْ، فَإِنَّ اللّٰهَ سَائِلُهُمْ عَمَّا اسْتَرْعَاهُمْ.
[Hazrat Abu Hurairahra narrated,] “The Holy Prophetsa said, ‘The Israelites used to be ruled and guided by prophets: Whenever a prophet died, another would take his place. There will be no [independent] prophet after me, but there will be Caliphs who will increase in number.’ The people asked, ‘O Allah’s Messengersa! What do you order us (to do)?’ He said, ‘Obey the one who will be given the pledge of allegiance first. Fulfil their [i.e., the Caliphs’] rights, for Allah will ask them about ruling those Allah has put under their guardianship.’”
(Sahih al-Bukhari, Kitab ’ahadithi l-’anbiya’, Bab ma dhukira ‘an bani isra’il)