Swiss Protestant theologian. He wrote his famous ‘Commentary on Romans’ (Der Römerbrief, ‘1919’, pub. 1918) while he was a pastor of Safenwil (Aargau). In this he revived Pauline and Reformation themes that had been muted in liberal theology—the sovereignty of God, the finitude and sinfulness of human beings, eschatology, and God's judgement on human institutions. In 1921 he became assistant professor at Göttingen and then professor at Münster (1925) and Bonn (1930). With the outbreak of the ‘Church Struggle’ in Germany (1933), he threw in his lot with the ‘Confessing Church’; the Barmen Declaration (1934) was largely his work. In 1935 he became professor of theology at Basle.
Barth aimed to lead theology away from what he believed to be the fundamentally erroneous 19th-cent. synthesis between theology and culture. Theology was to be based on the Word of God communicated in the Bible. Human reason, he held, has no power to attain to the knowledge of God which is given only in God's gracious revelation in Jesus Christ. This revelation comes from God to humanity and is contrasted with religion, which is described as human beings' sinful attempt to grasp God. This outlook rules out natural theology and makes any dialogue with non-Christian religions virtually impossible.
Apart from many other works, Barth devoted much of his life to a systematic exposition of his theology on a vast scale. The first volume of Die kirchliche Dogmatik (or Church Dogmatics, as it is known in English) appeared in 1932; the last section in 1967. This work, though unfinished, is the most detailed Protestant exposition of Christian doctrine to have appeared since the Reformation.