I believe in God. On most days. The chief reason for this belief is a collection of stories so odd that they're either clumsily made up or eternally true.

Had I been asked to write a book in order to trick people into monotheism, I would have concocted a tale a lot more consistent, logical, urbane, mathematically verifiable, politically correct, gender-inclusive, crosscultural, and family-oriented than what we call the Bible. That bit about God—our most devoted parent—asking Abraham to kill his son Isaac? Unhelpful. Cut. The ode to love found in the First Letter to the Corinthians, on the other hand—that's good stuff! I'd stretch it out to a whole book of love poetry and stick it in front of Genesis, to show why God bothered with humanity. And I'd try hard to get a quote from Jesus about homosexuals.

But God's book is already written, and—for reasons only he knows—the tricky passages remain. I tell myself, as G. K. Chesterton put it, that truth must be stranger than fiction, because "fiction is the creation of the human mind and therefore congenial to it." My wager's on the Great Uncongenial. In spite of its many riddles, God's letter to his children is an engrossing thriller about Love on a mission to ravish the world.

I trust in God because of the holy, universal body of Christ, too—in which weak-kneed people like me try to love God and others, but make mistakes all the time. That churches have multiplied (and not just because of splits)—from household fellowships in biblical times to Willow Creek Community Church—attests to the power of their creed. Then there are those three times in my 31 years so far that God answered my stubborn prayers so unambiguously that I felt like I'd just ...