From the beginning of this curiously ahistorical work, Birnstein's sympathies are clear. In the story of Michael Servetus, condemned for his anti-Trinitarian views by Catholics and Protestants alike and executed in 27 October 1553 in Geneva, encountered whilst writing a biography of Calvin, Birnstein identifies ‘remarkably modern insights into contemporary ecclesiastical and social debates’ (p. 8). In particular, he avers that ‘It is high time that there was a new discussion of the doctrine of the Trinity’, a doctrine which Bernstein views both as unbiblical and as problematic for interreligious dialogue. Bernstein's account of Servetus’ life is offered ‘in sympathy’ for one who, in his opinion, suffered a grave injustice at the hands of the Reformers. Birnstein traces Servetus’ life from his birth in 1511, probably in the Spanish town of Villanueva, to his early studies in Toulouse, his attendance at the imperial coronation in Bologna in 1530, his encounter with evangelical theology in Basel and Strasbourg, and his early doubts about the Trinity, published under the title De trinitatis erroribus in Hagenau in 1531, when Servetus was still only twenty. In the face of widespread condemnation of his views, Servetus fled to Paris, where he continued his studies in astrology, mathematics and medicine under the name Villanova and stood Calvin up at a planned meeting in 1534 (or 1536: Birnstein's chronology is unclear here). Moving to Lyon, Servetus, alias Villanova, produced a new edition of Ptolomaus's Geographical handbook (including the observation that the English had ‘recently fallen away from the Roman Church’: p. 42), and, having qualified as a doctor, was appointed surgeon to the archbishop of Vienne, Pierre Palmier. In Vienne, Servetus worked on a new edition of the Pagnini Bible, a revised Latin translation based on Greek and Hebrew texts, becoming ever more convinced that the doctrine of the Trinity had no biblical basis. In his Christianismi restitutio, which eventually appeared in January 1553 in Lyon, Servetus turned to (Platonic) metaphors of light to describe the relation of Christ and the Holy Spirit to God. He also rejected teachings on original sin, and with them the practice of infant baptism. The work led to Servetus’ identification, arrest and trial in Viennes. He fled from prison, but was condemned in absentia, and a portrait of him burned together with his works. Unwisely, Servetus travelled to Geneva, where on 13 August 1553 he was recognised, arrested, tried – Birnstein documents Calvin's involvement in the trial – and burned at the stake. A final brief chapter considers accounts of Servetus and his reception. Despite his clear biases, Birnstein draws on a commendable range of primary sources to make his case; however, the lack of footnotes means that these sources cannot be identified by the reader. There are several inconsistencies between Birnstein's account and his chronology of Servetus’ life (p. 96). Interesting aspects such as the views of the alumbrados in Spain or the influence of neo-Platonism on Servetus, are hinted at but not followed up. Birnstein's work makes clear that there is a fascinating study of Michael Servetus to be written, but someone else will have to do it.