Duties towards the Caliph
The Messenger of Allah (sal Allahu alaihi wa sallam) said, “Banu Isra’il were ruled by the Prophets. When one Prophet died, another succeeded him. There will be no Prophet after me. Caliphs will come after me, and they will be many.” The Companions said: “O Messenger of Allah, what do you command us to do?” He (sal Allahu alaihi wa sallam) said, “Fulfill the pledge of allegiance to which is sworn first (then swear allegiance to the others). Concede to them their due rights and ask Allah that which is due to you. Allah will call them to account in respect of the subjects whom He had entrusted to them.”
[Sahih Al-Bukhari and Muslim]
The political conduct of the Prophets means that rulership and government affairs were also assigned to them, that is, both religious and worldly affairs lay in their custody. There was no division between the two, they formed a single unit. This also characterized the period of the Rightly-Guided Caliphs and the short spell that followed it in the history of Islam. This explains why after the death of one Prophet, another Prophet came and was his successor.
This Hadith also settles the issue of the finality of Prophethood once and for all. “No Prophet will succeed me except the caliphs”, said the Prophet (sal Allahu alaihi wa sallam).
In the case of many claimants to caliphate, he also gave a ruling, that is, people should primarily fulfill their allegiance pledged to the first caliph and keep away from caring for another claimant to caliphate.
Also the Prophet (sal Allahu alaihi wa sallam) focused, on the lapses of rulers but without being suggestive of a rebellion against them. Instead he teaches us to obey them in the administrative sphere and also to turn to Allah and seek His Mercy and Blessing as long as they rule by the Law of Allah.
And Allah knows best!