The decade just passed has witnessed an unusual activity in the production of books about Martin Luther. This activity has been greatly stimulated by the re-introduction of a method of controversy which reasonable men had been hoping was forever silenced. Until about a generation ago there had been two obvious and hopelessly opposed ways of approach to the subject of Luther's character and work. From the one side he was presented as an angel of light; from the other as the type of a depraved and malicious spirit, moved to activity not through any desire to improve the condition of his people but because, being the malignant thing he was, he could not act otherwise. It need hardly be said to the readers of this Review that both of these views of Luther are essentially false. They are perfectly intelligible, one equally with the other. They are the natural precipitation of the bitter controversies that gathered about him in his life, and continued long after his death to complicate the political and economic struggles out of which the new Europe of our day was born. In the light of our modern historical method, both views appear crude and unscientific. They represent a way of looking at historical characters and historical events to which we are apt to apply the crushing word “old-fashioned.” And in fact it did seem, up to a very few years ago, that these primitive judgments, which classified men into good and bad, angels and fiends, had become a thing of the past.