Dietrich Bonhoeffer, The Cost of Discipleship

“The community of the saints is not an "ideal" community consisting of perfect and sinless men and women, where there is no need of further repentance. No, it is a community which proves that it is worthy of the gospel of forgiveness by constantly and sincerely proclaiming God's forgiveness...Sanctification means driving out the world from the Church as well as separating the Church from the world. But the purpose of such discipline is not to establish a community of the perfect, but a community consisting of men who really live under the forgiving mercy of God.” 
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