This article describes the background of the »Institut zur Erforschung und Beseitigung des jüdischen Einflusses auf das deutsche kirchliche Leben« (Institute for the Research on and the Elimination of the Jewish Influence in the Life of the German Church). Founded in 1939 by the radical wing of the »German Christians« in Thuringia, the institute sought to create a Bible, hymnal, and catechism free from Jewish influence. For Scripture, that meant no Old Testament at all and no Jewish elements in the New. Today it is common to see this project as a product of Luther's anti-Jewish writings, since Walter Grundmann, the institute's director, called their work »a legacy of Martin Luther«. Yet this article makes clear that Grundmann rejected Luther's anti-Jewish writings as fundamentally flawed, even »verjudet« (judaized), since in them Luther attempted to prove that Jesus was the Messiah. In Grundmann's view, this title had been falsely given to Jesus by his Jewish adherents. Rather than following Luther's anti-Jewish writings, Grundmann followed Houston Steward Chamberlain's »Die Grundlagen des 19. Jahrhunderts«, whose anti-Semitism was derived from Darwinism, while Chamberlain had no knowledge of Luther's anti-Jewish writings when he wrote his influential work. As regards the relationship with the Protestant churches, in spite of a massive output, the actual influence of the institute, which was supported by the Church of Thuringia and a few other German Christian churches, particularly the small church of the city of Lübeck, on German society during the war years was very limited.