In his wonderful Philosophy of Religion, Fulton J. Sheen expounds on several false assumptions underlying many studies of comparative religion. Here is a major one: is is commonly believed that the Divine and True Religion must be different from all other human religions. This is false, but I find it pervasive among both believers and skeptics, and hugely problematic.
For example, I often interact with those who think that if a biblical story has mythical elements or similarities to any non-historical religious tale, then the biblical story must be non-historical as well. The Christians who believe this spend their time trying to show that Christianity is completely different from pagan myths, sometimes having to stretch to ridiculous intellectual extremes to deny some of the obvious parallels. The skeptics who accept it emphasize these similarities as proof that Christianity is unhistorical, also working from the false premise that these parallels debunk biblical religion.
Both of these groups need to realize that it is entirely possible for a story to have mythical elements and similarities to non-historical tales and still be historical reality. Indeed, as C.S. Lewis rightly realized, in Christianity, myth became fact. Christianity is the fulfillment of the pagan myths. Christianity is that for which the pagan religions yearn. For example, there is a concept of redemption in many religions and pagan myths. Christianity also is focused on redemption. Does that mean Christianity is false? Of course not. The reason so many religions speak of redemption is because mankind actually needs to be redeemed. Christ is the one redeemer.
As such, Christians need to be willing to recognize the similar redemptive themes in many religions, and skeptics need to be willing to admit that these similarities do not rule out the historicity of Christianity. We don’t need to deny the history for the myth and at the same time we don’t need to deny the myth for the history.
That is not to say that there are not clear differences between Christianity and other religions. Sheen does an excellent job of explaining the transcendence of Christianity, but that is a point I will leave for another post.