Peter once shared his older brother’s views; he burned his Bible when he was a teenager in boarding school. But as he chronicled in his book, The Rage Against God — which he wrote as a response to his brother’s anti-religious book — he felt drawn back to his Anglican faith starting in his late 20s.

He says his work as a journalist in Somalia and the former Soviet Union persuaded him that civilization without religious morality devolves into brutality. Moral behavior requires more than higher reasoning, he says. It requires God.

“It seems to me to be very, very, very hard to come up with an atheistic explanation of conscience any more than you can have a compass with a magnetic north,” he says. “If the magnetic north kept shifting, then it would be very difficult to steer your boat or your plane across the Atlantic.”

Christopher Hitchens dismisses that argument — pointing out that much of the world’s evil is committed in the name of religion.