The main concern of the present article is to survey the issue of adopting religion as a voluntary or compulsory act. Voluntary act signifies man’s will to measure and choose when facing miscellaneous paths and options. Thus, measuring, making decision and choosing are accounted as three essential elements of voluntary acts.The followers of Ashareh sect believe that it is compulsory for all people to adopt religion as it is God’s gift to man; thus, man has no alternative save to adopt religion. Imamiyeh sect, on the contrary, stresses the adoption of religion as a voluntary act, referring to the common sense and holy Prophet’s traditions. They are of the opinion that every voluntary act enjoys at least three elements, including insight, tendency and power to choose. Accordingly, to prove their claim, they invoke the holy Quran verses and traditions for each one of these elements.