哈里发是代表乌玛行使统治权、权威，并执行神圣法律（沙里亚）的人。伊斯兰已经规定，统治权和权威属于乌玛。因此，乌玛应当任命一个人来行使这一权威，并代表乌玛执行神圣法律。安拉规定乌玛有义务执行全部沙里亚。由于哈里发是由穆斯林任命的，他就在统治、权威以及执行沙里亚规定方面成为乌玛的代表。除非乌玛向他献上效忠宣誓（拜阿），否则任何人都不能成为哈里发，因为统治权、权威和沙里亚的执行从根本上属于乌玛。乌玛通过向某人献上拜阿使其成为哈里发，实际上就是任命他为自己的代表。通过这一拜阿，哈里发国家的治权被委托给他，赋予他权威（苏丹），并使乌玛有义务服从他。

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. .

统治穆斯林的人，除非得到乌玛中有影响力之人（Ahl al-Hall Wa'l-Aqd）的效忠宣誓（Bay'ah），且此效忠并非出于强迫，否则不能成为哈里发。他必须具备哈里发应有的几项义务性条件，此后应着手执行伊斯兰教法（Shariah）的各项律例。

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.