I finished the above titled book by John Howard Yoder over a week ago and it has been one of the best reads in a long time. I would have to rate it up there with "The New Testament and the People of God" by N. T. Wright as one of the few great books in my life. "The Politics of Jesus" did not challenge as much paradigm restructuring as with Wright's book, since I was already familiar with most of Yoder's arguments, but it certainly helped clarify and unify a lot of the ideas that have been forming in my mind the past several years.
The book is composed of several essays, some of which could almost stand alone, but if I could sum up the essence of this work in one sentence, I would have to say that the underlying theme was that we must read the New Testament, and particularly the Gospels, with the recognition that Jesus ministry was very political in nature, and the ethic that he preached was not intended to be followed in a pious, individual sense, but as the written constitution of a brand new human social institution-the new humanity of the new creation order, the kingdom of God. The utter impracticality of this Way is precisely why the cross is such a stumbling block. And the church has historically under-emphasized the radical bits of Jesus' social ethic in favor of a system of law and order based upon "nature".
By "nature" I mean an approach to social ethics that may or may not be heavily founded upon biblical "principles" or even direct commandments (The Decalogue is a prime example.) The contrast with the politics of Jesus lies in the choice of whether to exercise one's sway in the various echelons of society, for good or for ill, or to deliberately pursue subordination, humiliation, and social imbecility.