In 1548 German Lutheranism seemed on the brink of collapse. Its founder had died, the emperor had won a decisive victory over the Protestant princes, and the resulting religious settlement forced liturgical compromise, dividing the movement into ‘conformist’ Philippists and ‘resisting’ Gnesio-Lutherans. Against this backdrop Matthias Flacius (1520–75) fought an explosive literary battle over the question adiaphora, or ‘things indifferent’, normally ecclesiastical rites neither repudiated nor recommended in Scripture. Two years later, the English clergyman John Hooper (1495–1555) engaged in a similar contest over adiaphora. His circumstances, however, were markedly different from those of the embattled Flacius. As a result of Lenten sermons before the king, he was offered the bishopric of Gloucester. Heedless of the gradualism of the Edwardine religious settlement, he refused to be consecrated in the vestments prescribed: a stand which brought him into conflict with Thomas Cranmer and Nicholas Ridley. Wade Johnson brings these controversies over adiaphora vividly to life. While both were fought against co-religionists, over the same issue, roughly contemporaneously, Johnson convincingly demonstrates that adiaphora ‘served as a lens’ for the broader theological frameworks of these two men as well as the circumstances in which they found themselves (p. xiv). Flacius’ stance was contextual (pp. 27–84); Hooper's was a matter of fundamental conviction (pp. 96–159).

There is much to admire in this study. Not only does this analysis offer a significant case study against the stereotype that Lutherans preached obedience while the Reformed developed resistance theories (p. xiv), but it also provides an excellent thematic consideration of Flacius’ use of outsiders in his polemical writing (pp. 62–8). Moreover, this text is written in a clear prose and peppered with entertaining turns of phrase (‘The devil, together with the whole papacy, was in the liturgical details’, p. 44). However, this book is not without flaws. It erroneously notes that Hooper served ‘as a bishop until his death under Edward vi’ (p. xiv): a sentence presumably meant to read ‘until the death of Edward vi’ in light of numerous references to Hooper's Marian martyrdom elsewhere in the book (pp. 103, 105, 116, 120, 169). Likewise, this survey makes much of Alec Ryrie's evocation of the ‘strange death’ of Lutheran England but fails to take into account the fact that Ryrie himself has recently nuanced this thesis (‘The afterlife of Lutheran England’, in Dorothea Wendebourg [ed.], Sister Reformations: the Reformation in Germany and England, Tübingen 2010, 213–34). Issues like these give the impression that Johnson is less at home in scholarship pertaining to the English Reformation. He has, none the less, produced a useful comparative analysis, which will undoubtedly be of service to those considering Reformation debates over adiaphora.