Karl Barth (; German: [baɐ̯t]; (1886-05-10)10 May 1886 – (1968-12-10)10 December 1968) was a Swiss Reformed theologian who is most well known for his landmark commentary The Epistle to the Romans (1921) (a.k.a Romans II), his involvement in the Confessing Church, and authorship of the Barmen Declaration, and especially his unfinished five volume theological summa the Church Dogmatics (published in twelve part-volumes between 1932-1967). Barth's influence expanded well beyond the academic realm to mainstream culture, leading him to be featured on the cover of Time on 20 April 1962 and Pope Pius XII said Barth was “the greatest theologian since Thomas Aquinas.”Barth's theological career began while he was known as the "Red Pastor from Safenwil" when he wrote his first edition of his The Epistle to the Romans (1919) (a.k.a Romans I). Beginning with his second edition of The Epistle to the Romans (1921), Barth began to depart from his former training – and began to garner substantial worldwide acclaim – with a liberal theology he inherited from Adolf von Harnack, Friedrich Schleiermacher and others. Barth influenced many significant theologians such as Dietrich Bonhoeffer who supported the Confessing Church, and Jürgen Moltmann, Helmut Gollwitzer, James H. Cone, Wolfhart Pannenberg, Rudolf Bultmann, Thomas F. Torrance, Hans Küng, and also Reinhold Niebuhr, Jacques Ellul, Stanley Hauerwas, and novelists such as John Updike and Miklós Szentkuthy. Among many other areas, Barth has also had a profound influence on modern Christian ethics. He has influenced the work of ethicists such as Stanley Hauerwas, John Howard Yoder, Jacques Ellul and Oliver O'Donovan.
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Though it is possible to utter words only with the intention to fulfill the will of God, it is very difficult not to think about the impression which they will produce on men and not to form them accordingly. But deeds you can do quite unknown to men, only for God. And such deeds are the greatest joy that a man can experience.