difficulty of definition of religion and approaches

as we know, at the course of history of thought the definition of religion has been always a significant dilemma and each thinker or philosopher of religion had inclination to present an accurate definition of religion. in spite of these attempts, there has been no consentaneous definition of religion up to now. difficulty of the definition of religion has several reasons that in this article some of them are mentioned. in addition, in spite of improbability of definition of religion, in this paper we will present a definition which presumably there would be a common agreement on it. among these common approaches to the definition of religion, the theory of family resemblance, which belongs to wittgenstein, and alston’s approach are notable. these approaches although are not perfect formulas; but in comparison with other approaches can be more plausible.