Carlos Eire in The New York Times:
Eric Metaxas is exceedingly bold, for writing a biography of Martin Luther has always been a great challenge. To begin with, becoming a Luther expert requires a lot of reading. Jaroslav Pelikan, the eminent church historian who served as an editor of the American edition of Luther’s Works, often warned his students that more books had been written on Luther than on any other figure in Christian history, save for Jesus Christ. Add to this colossal bibliography the scores of huge tomes filled with Luther’s own writings in German and Latin, and the effort required for summing up his life and work will seem even more daunting.
But writing a Luther biography in 2017 is a special challenge, perhaps among the greatest any author can face, at least with regard to the competition from other authors. This is the 500th anniversary of Luther’s Reformation, so whether one likes it or not, we are all living through the “Year of Luther,” or Lutherjahr, as it has been called in his native land; publishers in Europe and North America are marking the occasion by flooding the world with Luther biographies. In the first 10 months of this year, over a dozen English-language biographies have appeared, including one in comic book form and one aimed at children. And all of these follow on the heels of at least another half-dozen magisterial biographies published in the past two decades, including Martin Brecht’s exhaustive three-volume masterpiece, “Martin Luther,” which Metaxas praises as “unsurpassable.” Needless to say, such excess could easily stun any reader, cause an outbreak of fatigue — Lutherjahrmüdigkeit as Germans might say — or scare away all would-be Luther biographers for years to come.
Most new Luther biographies are by historians who are Reformation specialists and, as one might expect, they have been aimed at an academic audience, even when written for trade publishers rather than university presses. Whatever fresh insights these biographies can claim rest more on interpretation than on the discovery of new facts.