Khalifah shi ne mutumin da yake wakiltar Al-Ummah wajen mulki, iko da aiwatar da dokokin Allah (Shari'ah). Musulunci ya tabbatar da cewa mulki da iko na Al-Ummah ne. Saboda haka, al-Ummah ce za ta zabi wani mutum da zai tafiyar da wannan iko tare da aiwatar da dokokin Allah a madadinta. Allah ya wajabta wa Al-Ummah aiwatar da dukkan Shari'ah. Tun da Musulmai ne suke nada Khalifah, hakan ya sa shi wakili ne na Al-Ummah wajen mulki, iko da aiwatar da hukunce-hukuncen Shari'ah. Babu wanda zai zama Khalifah sai Al-Ummah ta ba shi mubaya'a (Bay'ah), domin mulki, iko da aiwatar da Shari'ah na Al-Ummah ne asali. Ta hanyar ba wa mutum mubaya'a a matsayin Khalifah, Al-Ummah tana nada shi a matsayin wakilinta. Ta wannan mubaya'a ne ake mika masa daular Khilafah, wanda hakan ya ba shi iko (Sultan) tare da wajabta wa Al-Ummah yi masa biyayya.

The Khalifah is the man who represents the Ummah in ruling, authority and in the implementation of the Divine laws (Shariah). Islam has decreed that ruling and authority belong to the Ummah. It is therefore for the Ummah to appoint an individual to administer that authority and apply the divine laws on her behalf. Allah made it obligatory upon the Ummah to execute all of the Shariah. Since the Khalifah is appointed by the Muslims, this makes him a representative of the Ummah in terms of ruling, authority and in the implementation of the Shariah rules. No-one can become a Khalifah unless the Ummah has given him the pledge of allegiance (Bayah) because ruling, authority and the implementation of the Shariah belong to the Ummah in origin. By giving Bay’ah to a man as Khalifah, the Ummah effectively appoints him as her representative. Through this Bayah the Khilafah state is delegated to him, giving him the authority (Sultan) and obliging the Ummah to obey him. .

Mutumin da yake mulkin Musulmi ba ya zama Halifa sai an ba shi Bai'ah daga manyan mutane masu tasiri (Ahl al-Hall Wa'l-Aqd) daga cikin Al'umma, ba tare da tilastawa ba. Dole ne ya cika wasu sharuddan wajibi na Halifa, sannan ya ci gaba da aiwatar da hukunce-hukuncen Shari'a bayan haka.

The man who rules the Muslims does not become Khalifah unless the Bay’ah is given to him by the influential people (Ahl al-Hall Wa’l-Aqd) from amongst the Ummah, without compulsion. He must fulfil certain obligatory conditions for a Khalifah and should proceed after that in implementing the rules of the Shariah.