This book, published posthumously in 1994 is attempt to crticially study if there is such a thing as a Two Kingdoms doctrine in Luther. That Luther writes about two kingdoms and uses this as a tool in his thinking about church and world is clear, but does this thinking have the consistancy and coherence needed for it to be considered a doctrine, and consequnetly binding for those that want to follow Luther? For Frostin the answer is clearly no. I find the following reasons the most important:
1. The dubious background of the ”Luther’s two kingdoms doctrine” as doctrine. The concept of such a doctrine is fairly recent, the term was coined in the late 19th century and became a central notion in the 1930:s Germany. Yep, Nazi-Germany. Essentially it was developed in order to justify that the Christians accepted Hitler’s rule. This is relevant not so much for guilt by association purposes, but it clarifes the political significance of the doctrine. It is a way to stop the church from criticising worldly power.
2. Luther’s use of this ”tool” is far from stable. It changes enormously over time, and Frostin makes a particularly fine job showing how earlier texts by Luther has been interpreted using later texts and modern questions. Also in practice Luther seems to ha shifted positions liberally, from at times coming very close to Christian pacifisim to the notorious ”Kill them all” haranges against the peasant rebels.
3. The way this ”doctrine” is most often intrepreted today, that is that the church should not be politically active, or at least should not try to argue theologically in political matters at any rate finds little support in Luther. In fact he saw critcism of worldly power as an important part of preaching and he was very active himself in political situations. The modern idea that (secular) reason and natural law are the only sources for social ethical reflection is alian to Luther.
So, I learned a lot from this book, and would recommend it, in spite of the a times very bad english, no part a result of its unifinished status at the time of the death of prof. Frostin.
Still. Luther is IMO way to complex a figure for anyone, not to mention the church, to try to build upon.