This work examines, critically, an East German theologian, Hanfried Muller, professor of theology at the Humboldt University in East Berlin and a committed Marxist. Specifically, the role of political ideology in Muller's theology, in general, and his views of the church, in particular, are explored. While the influence of Dietrich Bonhoeffer and Karl Barth on Muller are of major importance to Muller, it is argued here that his use and interpretation of them is shown to rest, in large part, on his ideological convictions. It is argued that Muller's Marxist perspective reflects a new direction in the Christian socialist tradition that began in the nineteenth century. Finally, this dissertation maintains that Muller's ideology replaces the traditional notion of ecclesiology, not only in Bonhoeffer and Barth, but for most of his contemporary theologians.