The Gospels say that the kingdom is present and yet to come. Biblical faith recognizes the worth of this world. It does not ask us to escape from history. So, in this sense, God's reign is here already to some extent. At the same time, the kingdom remains in the future.
History can never be perfect.
Because of finitude and sin, we cannot realize the ideal. For Niebuhr, the consummation of history lies beyond the temporal process. There will never be a messianic millennium in history. Christians affirm the ultimate sovereignty of God and the final supremacy of love, but they do not deceive themselves by thinking that these can take place within finite, temporal conditions. Emil Brunner's doctrine of Christ represents a typically modern expression of Reformation theology.