Rainer Florie's study of the important Jesuit moral theologian and professor of canon law Paul Laymann (1574–1635) is based on his 2016 dissertation. In places the book reflects its origins, containing long and fairly unoriginal explanations of the political contexts of Laymann's life and work. On the other hand, this study also includes important and interesting insights about this influential thinker.

Very little is known about Laymann's biography, other than the positions that he held, the works that he published, and the basic information contained in Jesuit administrative records. Florie thus has little opportunity to engage with Laymann's personality or social background. As a consequence he has written what is essentially an intellectual biography, focusing understandably on Laymann's writings. This in turn means that the book is about three main areas of Laymann's work: writings on moral theology, works on the question of the prosecution of witches and the political/constitutional works produced in Laymann's last years.

Florie emphasises that Laymann was best known, at least within Catholic circles, as the author of a Theologia moralis of 1625. The book was written as a textbook for courses and as a handbook for pastors. Here Florie traces the intellectual tradition within which this book falls, particularly the influence of Aquinas and how his moral theology fits in the Jesuit pastoral tradition. Laymann emphasises the importance of the conscience and the idea that a confessor should treat his flock with patience and consideration. His book remained in use for decades and, Florie argues, was broadly influential with later moral theologians.

Laymann was active in the intellectual debate around the issue of witch trials, a debate that split the Society of Jesus. Florie points out that it was initially difficult for Catholic writers to oppose witch trials, since earlier opponents, particularly Johann Weyer, were Protestants. Laymann himself became involved in the high-level disputes around the hunting of witches in Munich in the first years of the seventeenth century. Apparently not a person to take a leadership role at this stage of his career, Laymann followed the example of Adam Tanner, the first Jesuit to condemn the trials.

Laymann advocated moving carefully against witches and sorcerers. Florie lays out Laymann's position clearly. He insisted on the application of imperial law, rather than local laws. Like Tanner, he deployed biblical and theological arguments to say that ‘God does not allow that an innocent person should be questioned along with a guilty person and when it is discovered that the innocence has been hidden, it should not lead to being sentenced to a shameful death’ (p. 158). Laymann also lamented the tendency to spread blame to family members or even whole communities, leading to severe social chaos. As a teacher of moral theology, Laymann emphasised that reliable evidence against witches was hard to find. Most of all, however, he wrote of the duty to ‘kill no innocent people’ (p. 160). While hardly a radical position, Laymann did lend his prestige to those who opposed the trials and Florie argues that he was an important predecessor of the influential Friederich von Spee, the Jesuit credited with undermining the witch craze after 1630.

If Laymann looks progressive on the issue of witches, he was a strong supporter of the most militant Catholic political positions during the Thirty Years’ War. His Pacis composito of 1629 laid out a series of legal and constitutional arguments – a toolkit for Catholic extremists – that were then used to support the Edict of Restitution of that year. Florie argues that Laymann's work, co-written with other professors at the University of Dillingen, was a legal text rather than a polemical work, and thus had more staying power than most tracts written in this period. Laymann, for example, advocated clear treaties and careful legal structures within the Holy Roman Empire, which had influence on the Peace of Westphalia in 1648. Laymann may have written as a jurist, but the Swedish King Gustavus Adolphus listed him as one of three Jesuits whom he wanted to hang, along with Wilhelm Lamormaini, confessor to Emperor Ferdinand, and Laurentius Forer, a theologian and polemicist. This Protestant hero considered Laymann a dangerous warmonger (p. 5).

Florie's study brings together the different strands of Laymann's life and work. His well thought out conclusion points to the fluidity of his thinking and his evolution as a writer. Laymann was also fully integrated into the Jesuit network, aware of developments within the Society and often contributed to those discussions. These important insights are part of a careful and thorough study, deeply imbedded in German historiography. Florie does use the important work of the American scholar Robert Bireley and a number of other English language works. Unfortunately, he has neglected several important (non-German) scholars of the Jesuits, particularly Louis Châtellier and John O'Malley. Despite this weakness, Florie has produced a useful and often illuminating study of an important figure.