What lies under the theory of authority of Shiite thinking is the belief that Ali was qualified for the leadership of muslim community after the prophet?s death.Accordingly they attributed a kind of holiness to the Imams and depicted them immune to sin like prophets, which is totaly against Qur?anic principles. The following article is  to outline the historical background of this teaching especially under the period of Rightly Guided Calips (Hulafa ar-Rashidin) and afterward