Two Kingdoms and the Great War

Philip Jenkins makes an insightful point about Lutheran two-kingdom theology and the Great War in his book The Great and Holy War:

German Protestants of this generation, though, had remarkably few qualms about presenting violence and warfare as legitimate tactics for a Christian state. Through its Zwei-Reiche-Lehre (two-kingdoms doctrine), Lutheran theology taught that the two kingdoms, earthly and heavenly, each had its own moral codes and ways of being. Although Christians lived in both simultaneously, it was impossible to apply the absolute demands of New Testament ethics to each: the state simply could not be expected to operate according to such standards. A state that turned the other cheek in the face of aggression or invasion would soon cease to exist. Even a nation made up almost entirely of devout Christians could never act politically according to strict Christian moral teachings. Potentially, this approach justified cynical state actions that seemed to violate Christian teachings or commonly accepted moral standards. In 1914, the doctrine overrode objections to the treatment of Belgium.

Philip Jenkins, The Great and Holy War: How World War I Became a Religious Crusade (New York: HarperCollins Publishers, 2014), 84-85.