The belief in a savior who establishes justice and removes injustice in the world is an essential doctrine for Shiite Muslims and is a belief held by all Muslims. In Shiite doctrines, this promised savior has also been called al-Qa'im (person who rises) from the family of Muhammad (s).
According to hadiths, the Prophet (s) predicted that a man from his household, called "al-Mahdi" (the guided one), will appear and fills the earth with justice, as it was filled with injustice. Thus after the demise of the Prophet (s), Muslims always expected the appearance of al-Mahdi (a).
Mahdawiyya contains several issues, including,