Without the tragedy of the destruction of Jerusalem, Rome might never have taken the unique place which it has held in the story of Western Christian faith. But no one would have realized this even two centuries after the death of Jesus Christ; and for centuries more there was as much likelihood of Christianity spreading as strongly east as west from the ruins of Jerusalem, to become the religion of Baghdad rather than of Rome. That is why the next stage of this story will take us east, rather than in the westward and northward directions so often chosen by the historians of Christianity.