Since Islam is the last religion, its tax systems are everlasting and in effect until doomsday. On the other hand, the establishment of a government by Prophet Muhammad (PBUH) is the best proof of relation between religion and politics. In addition to having the duty of prophet hood and promoting Islam, Muhammad (PBUH) was also appointed to the position of Imamat:
“when Abraham was tried by his Lord with commands and he fulfilled them. [Allah] said, “Indeed, I will make you a leader for the people.” (Baqara, 124) – And leadership – “O you who have believed, obey Allah and obey the Messenger and those in authority among you.” (al-Nisa: 59) and had the mission to establish government. Other prophets also had this mission. “O David, indeed We have made you a successor upon the earth, so judge between the people in truth” (Sad: 26)
Religious scholars, including theologians and jurisconsults, have included managing and reforming religious and secular affairs in their definition of Imamat. This view was prevalent among Muslim scholars until last century. When the notion of secular government was introduced into Islamic societies by the west, the issue of separation between politics and religion became popular among westernizer intellectual circles.
Reviewing religious texts and conducts of the Muslims with regards to the issue of government shows that in addition to providing security, enforcing laws and protecting people’s life and assets, the theocracy also has the duty to enforce religious values and objectives.