The later Wittgenstein believes that if we want to understand religious beliefs, we should know and get involved with the two concepts of language games and forms of life (which he uses to describe his teachings). In fact, it can be said that his understanding of the rationality of religious beliefs is one based on language games and forms of life. In other words, the rationality of religious beliefs is given its meaning by these two metaphors. Therefore, if one wants to make rational his religious beliefs, he should understand this rationality in the context of forms of life. That is to say, if a religious person has based his religious beliefs in the context of forms of life, then his religious beliefs is rational from the viewpoint of the later Wittgenstein. As a result, the meaning of rationality in religious beliefs should not be taken and judged the same as the meaning of rationality in science. According to the later Wittgenstein’s viewpoint, our religious beliefs do not need any justification – either rational or historical – and an individual who tries to rationalize the religious matter based on another language game’s rules is in fact an irrational person, because he is totally unaware of the station of religious beliefs. In this article, we aim to both explain the later Wittgenstein’s viewpoint to the rationality of religious beliefs and explicate the current criticisms and shortcomings of the concepts such as language games.