In his commentary The Epistle to the Romans (Ger. Der Römerbrief), particularly in the thoroughly re-written second edition of 1922, Barth argued that the God who is revealed in the cross of Jesus challenges and overthrows any attempt to ally God with human cultures, achievements, or possessions. Many theologians and religious historians believe this work to be the most important theological treatise since Friedrich Schleiermacher's On Religion: Speeches to its Cultured Despisers.
In the decade following the First World War, Barth was linked with a number of other theologians–actually very diverse in outlook–who had reacted against their teachers' liberalism, in a movement known as "Dialectical Theology" (Ger. Dialektische Theologie). The members of the movement included Rudolf Bultmann, Eduard Thurneysen, Eberhard Grisebach, Emil Brunner, and Friedrich Gogarten.
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