Politics and Faith interprets the partnership of Reinhold Niebuhr and Paul Tillich by exploring their relationship and mutual influence. Ronald H. Stone draws upon a survey of their students, their published English and German work, their letters, their organisations, the Federal Bureau of Investigation's files, and his relationship with them, their families, and colleagues to provide a fresh account of their work and life in New York City. They were shaped by their service in World War I, their development in revolutionary Germany, and in New Deal America as the two empires prepared for their second war. Allies in World War II against Hitler, immediately after the war they were thrown into interpreting the cold war world. Neither would live to see it climax in Tillich's beloved Berlin.

Stone's unique perspective derives from his study with these two men and his service as Reinhold Niebuhr's last teaching assistant. Knowing them from their preaching provided an intimate glimpse into their spiritual life. During his teaching career, Stone served as president of the North American Paul Tillich Society and was a founding board member of the Niebuhr Society. He previously edited or authored seven books on his mentors while teaching about them at Union and Pittsburgh Theological Seminaries, Vassar and Morningside Colleges, and Columbia, Duquesne, Pacific Lutheran, and Pittsburgh Universities.

The differences between Niebuhr and Tillich in theology and philosophy produced an alliance in social thought and politics. Despite one third of the book considering the many criticism of their work, Stone finds the two producing the most adequate faith-based political philosophy for the guidance of the American Empire in the twenty-first century.