Muslim and Mu'min
Source: Ain-al-Hayat, By: Allama Muhammad Baqir Majlisi
Imam Ar-Reza (as) says, ďFaith (Iman) means professing through the tongue, understanding it through the heart and manifesting it through the acts of all the parts of the personís body!Ē
Imam Ar-Reza (as) says a Muslim is not necessarily a Muímin nor a Kafir. The only benefit he derives from professing Islam is that his execution is not permissible. Nor is he considered Najis (unclean). People can eat and drink in his company, can have matrimonial relations with him. Such a Muslim does not believe in the Day of Reckoning that he has to prepare for that day!
Contrary to the above, a Muímin, according to the definition given by the Prophet and the Imams (as), professes his Faith publicly, practices it implicitly and holds the Faith strongly in his heart. The Muímin deserves Allahís Rewards, qualifies for the Prophet (S)ís Intercession on the Day of Judgement and will not be consigned to the Hell forever if he had committed some sins in his worldly life. His righteous deeds and prayers during his life will not go in vain.