The concept of 'Velāyat-e faqīh' as a form of Shia Islamic rule became popular after the Islamic revolution in Iran and is the most important and dominant institution in the system of governance of the Islamic Republic of Iran. The Islamic revolution was a radical and far-reaching change in Iranian society, aimed at overthrowing the Shah and establishing a new system of government based on both Sharia and civil law. The political, economic, and cultural future of the state was determined by Shia clergy after the 1979 Islamic Revolution in Iran. Ayatollah Ruhollah Khomeini established a social society based on Islamic religious principles and developed a theory of state development. After the victory of the Islamic revolution, Ayatollah Ruhollah Khomeini put forward the theory of defending "Islamic power" as a religious priority, thereby strengthening the foundations of the religious state. The concept of 'velayat-e faqih' was an opportunity for a solution to the crisis of legitimate state authority in Shi'ism. It has enshrined in the Constitution of the Islamic Republic of Iran and is the basis of the state structure of the country and has the closest connection and similarity with the Imamate system.