The Jungian reading of religions is close to Gnosticism, which is heretical in Christianity. The idea is that we have a divine spark that's supposed to be expressed as a light in the darkness (in the demiurge's shadow world). We should be following our spiritual rather than our fallen, natural self. Jesus's death and resurrection are thus metaphors for how we should die to our natural self and be spiritually reborn, as we recognize our identity as divine beings (or as minds that encompass the unconscious archetypes).

Official Christianity, by contrast, literalizes and historicizes the myth. So the question is which Christianity is genuine, the esoteric or the exoteric, the metaphorical/mythical or the literal/historical?

The more we emphasize the mythic and pagan connections, the less we're treating the origin of Christianity as a series of unique supernatural events in history. Thus does comparative mythology conflict with mainstream Christianity.