When my Yale colleague Professor Carlos Eire visits his elderly mother, he often ends up as a resident theologian for a small Cuban-immigrant community of her friends. "Is it possible," one woman asked him, "for Castro to convert on his deathbed and end up in heaven?""It is possible," Professor Eire assured her. "This is what Christian faith is all about. Nobody is beyond the pale of redemption.""Well, if that were to happen," said the woman, "then I would not want to be in heaven."Karl Barth was once asked the antithesis of that Cuban expatriate's question: "Is it true that one day in heaven we will see again our loved ones?" Barth responded with a chuckle, "Not only the loved ones!" The sting of the great theologian's response—be ready to meet there even those whom you dislike here—was directed against our propensity to populate heaven only with people whom we like.Most of us have our own "Castros" with whom we would rather not share the space of the world to come. Heaven with them, we imagine, would feel more like a forecourt of hell.This dilemma contains a serious personal challenge and, it turns out, an inadequately addressed theological issue. How can those who have disliked or even had good reasons to hate each other here come to inhabit together what is, in Jonathan Edwards's memorable phrase, "a world of love"?The not-loved ones will have to be transformed into the loved ones, and those who do not love will have to begin to do so. Enemies will have to become friends. Sometime between a shadowy history and an eternity bathed in light, somewhere between this world and the next, a transformation of persons and their complex relationships needs to take place. Without such a transformation, the world to come would not ...