After "Constantianism" Supposedly Established, St. Ambrose Excommunicates Caesar

Sometimes our formulations are too easy. When Protestants do history I think we should be especially on guard because, let's face it, our propensity is to slough off the effort from a long tradition of neglect of history between Augustine and Luther, or beyond. For instance, in the case of the charge that since Constantine the church has succumbed to "Constantinianism" and "doing ethics for Caesar" has to be mitigated if not thrown out when actual intricacies of history are look at seriously. Take for instance the following case which occurred almost 90 years after Constantine has become emperor:

"When, in the year 390, Saint Ambrose excommunicated the Christian Theodosius for his massacre in Thessalonika, he was holding Caesar accountable to the ethics of the Church". A more correct view seems to be the following:

"The history of the relations between the church and the state in the Middle Ages is a history of a long dispute waged with wavering fortune on either side. Extravagant claims on one side called forth equally extravagant claims on the other. The Eraastianism of post-Reformation settlements was the answer to earlier imperiousness on the other side" (p. 34, American Babylon, 2009, Richard John Neuhaus).