Karl Barth was one of the greatest Christian thinkers in the twentieth century. Some think that his multi-volume Church Dogmatics is the most vigorous re-statement of essential Christianity produced in the last century. I remember when I first began to read it. It took me awhile to appreciate Barth because I had been told so many things about him by fundamentalists who thought that he was an enemy of the faith. When I began to read his work I was stunned at the care with which Barth handled the Bible. His thought was saturated with Scripture. Barth had a lot to say about the church but one of the finest statements I have read captures my attention whenever I read it. Consider Barth's thoughts:
There is no escape-hatch from the visible to the invisible church . . . Nor should we try to explain the multiplicity of churches as something willed by God, the normal unfolding of the grace given to mankind in Jesus Christ. . . . To do so, however attractive it might seem would be to construct a philosophy of history or society, nor a theology. In other words, to solve the question of Church unity, we would be constructing our own ideas instead of listening to the question as it is put by Christ and hearing Christ’s own answer. . . . If we listen to Christ, we do not live above the difference that divide the churches but in them. [Which leaves us with only one painful alternative:] We should not try to explain the multiplicity of churches at all. We should treat all of it the way we would treat our own sin and those of theirs: as sin. We should see it as part of our guilt. [We] can only be shocked by these divisions and pray for their elimination.” [emboldening mine].
Die Kirche und die Kirchen (1935); cited by Hans Urs von Balthasaar in The Theology of Karl Barth (San Francisco, California: Ignatius Press, 1992, 4).