Marcus Borg is killing me. Ok, just making me wrestle with issues. Still, it hurts.

From "The Heart of Christianity":

Seeing this commonality between the way of Jesus and the ways of the world’s religions is sometimes disconcerting to Christians, given our history of “Jesus is the only way.” But the commonality is cause for celebration, not consternation. Not only does it mean, to echo an exclamation in the book of Acts, the Spirit has gone out to Muslims, Buddhists, Jews, Hindus, and so forth, but it also adds credibility to Christianity. When the Christian path is seen as utterly unique, it is suspect. But when Jesus is seen as the incarnation of a path universally spoken about elsewhere, the path we see in him has great credibility. (Read the excerpt in context here.)

So to Marcus Borg, a rubrick for determining "truth" is commonality across religions. I can see this, as a loving God would want to reach out to all, and welcome all into relationship.