Hence there is a certain “political” character involved in the idea of sanctification and it is this character which provides the only basis for the Church’s political ethic. The world is the world and the Church the Church, and yet the Word of God must go forth from the Church into all the world, proclaiming that the earth is the Lord’s and all that therein is. Herein lies the “political” character of the Church. If we regard sanctification as a purely personal matter which has nothing whatever to do with public life and the visible line of demarcation between the Church and the world, we shall land ourselves inevitably into a confusion between the pious wishes of the religious flesh and the sanctification of the Church which is accomplished in the death of Christ through the seal of God.
Dietrich Bonhoeffer, The Cost of Discipleship, 280.