Yet when even the pope wonders aloud as to whether it’s appropriate for him to judge, you begin to see the difficulty of deciding what “true Christians” ought to believe. This raises the question of whether the religiously based principles are merely cultural artifacts that we bend to our own immediate purposes.

The answer lies in embracing a humility about how imperfectly human beings understand the divine, which is quite different from rejecting God or faith. This humility defines the chasm between a living religious tradition and a dead traditionalism. We need to admit how tempted we are to deify whatever commitments we have at a given moment. And those of us who are Christian need to acknowledge that over the history of the faith, there have been occasions when “a supposedly changeless truth has changed,” as the great church historian and theologian Jaroslav Pelikan put it.

What distinguishes this view from pure relativism is the insistence that truth itself exists. The Christian’s obligation is to engage in an ongoing quest for a clearer understanding of what it is. Robertson would disagree with me, but I’d say that we are going through precisely such an effort when it comes to how we think about homosexuality, much as Christians have done before on such matters as slavery, the role of women and the Earth’s place in the universe.