Legality of a Government and Its Principles in Islam and Western Thoughts

In brief, legality means the right for governing over a nation or community. In this paper, presenting and analyzing the definition of legality, its fundamental principles have been attended to in details and its essential difference with the political view of Islam has been studied.
      In general there can be found four main theories in the field:
A-       Morality, in this theory it is argued that moral values are counted as a basis for political obligations. Plato has been known the founder of this theory.
B-        Theory of power, Machiavelli and Hobbs from the West and Gazzali and Shafei from Muslim scholars have agreed with the theory.
C-        Liberal democracy, it is a well-known theory ruling over western societies nowadays. On this theory, it the demand and vote of majority of citizens that causes legality. The theory was originally founded in the west by John Lock and Rousseau.
D-       Shiite theory, presented by the late Imam Khomeini; in this theory, the right for sovereignty is originally known to be restricted to God and He has delivered it to prophets, their true successors and religious scholars of the most level in religious knowledge and purity.
      Finally a short comparison has been made between the last theory and the others.