The 500th anniversary, in 2017, of Martin Luther’s (probably mythological) nailing of 95 theses on a door inspired many conferences, exhibitions, re-enactments, and the publication of a number of imposing monographs. The English-speaking world has been introduced to Heinz Schilling’s biography of Luther.Footnote ¹ Andrew Pettegree discussed how Luther’s ‘brand’ spread across Europe through an intense publishing campaign.Footnote ² Peter Marshall studied the mythmaking around the man.Footnote ³ Lyndal Roper’s biography showed Luther in flesh-and-blood.Footnote ⁴ These are but some of the key publications which this commemorative year generated. Among this list belongs Richard Rex’s The Making of Martin Luther, which concentrates on Luther’s intellectual journey.

Rex focuses on the few years surrounding Luther’s excommunication by Pope Leo X in 1521, a time during which he transformed from medieval thinker into the founder of a new Church. Focusing on the early years of Luther’s life in public, Rex does not dwell much on the practicalities and implications of this thinking. It is a history of ideas, which is not to dismiss the reading of Luther through the lenses of social and cultural history. Rex’s focus on the history of ideas translates itself in the structure of the book. Most chapters centre around a key idea or debate which Luther thinks through until—and including—his confrontation with Erasmus in 1525.

Rex discerns the development through which Luther came to express the thoughts which would inspire the new Church, grounding him firmly in medieval thought and the contemporary cultural landscape that shaped him. Rex does not attempt to read retrospectively the more mature Luther into his early writings or anticipate an inevitable path to a break with Rome. Rex believes ‘such efforts are misplaced, and depend either on misunderstanding the distinctive character of Luther’s mature theology or misunderstanding late medieval catholic theology (or both)’ (p. 48). Rather than searching Luther’s early writing for the germs of his later, mature, thoughts, Rex maps a gradual shift away from a conventional thinker.

Indeed, Rex presents Luther as a thoroughly medieval thinker. Using Luther’s lecture notes and marginalia to track his earliest ideas, Rex does not identify any particularly novel reading of the Bible until the mid-1510s. Luther broke with medieval traditions and set himself against them; however, at the same time he could not avoid immersion in them since the issues he was grappling with were medieval debates and concerns—even if his answers broke new ground. Or, as Rex eloquently puts it, ‘Luther’s problems were medieval problems, but his solutions were new solutions’ (p. 223). His early writings reiterated criticisms which were widely-shared: as Rex points out ‘Reformist critique was an orthodox genre’ (p. 37).

Luther’s thinking could not have developed without the discussions among scholastic theologians. Notably, his understanding of justification was fermented in the scholastic theory of indulgences. He laboured through the reasoning behind the doctrine of indulgences, and then, after arguing that the theory went too far, he would come to argue that it did not go far enough and assert that universal indulgences were called for. As Rex put it, ‘Luther’s doctrine of justification was not so much a reaction against the theory of indulgences as its culmination’ (p. 21). Underpinning the theory of indulgences is the conception of Christ’s merits. Luther took that thought to its extreme conclusion and argued that salvation was guaranteed solely through Christ’s merits—‘the doctrine of justification by faith alone was simply the proclamation of universal, plenary indulgences, available at absolutely no cost or effort’ (p. 20).

At the heart of Rex’s reading of Luther’s ideas stands ‘certainty’. Luther may have toppled a system of thought and practice that had been in place for a long time through questioning and doubting, but this was not, in Rex’s reading, his default characteristic. ‘If he called things into doubt, he did so in the name of certainty’ (p. x). Christians had to be certain they were saved. This was the key to his theology and the conviction that ensured the break with Rome. As a consequence of the Bible being a certain source of truth, Christians had to display an ‘unwavering and absolute certainty of the immediate enjoyment of the grace and favor of God’ (p. 10); this was the cornerstone of Luther’s justification by faith alone.

Rex’s identification of certainty as the key to Luther’s theology leads him to pinpoint 1518 as the decisive year, rather than 1517. This was the year in which Luther gained notoriety when the 95 theses were printed and widely distributed, but, more crucially, this was the year in which he studied and preached on the story of Abraham. He extrapolated his interpretation of Christian life from the story of Abraham’s two sons: one, Ishmael, born out of wedlock with Haga, and one, Isaac, begotten with Sara in her old age. Isaac was the son born to Abraham and Sara out of God’s grace in reward for Abraham’s unwavering faith. Luther mapped his own life trajectory onto this story. Whereas he had been a ‘son of Haga’ for 35 years, hoping, but never being certain, to be saved through worldly works, once he became son of Sara he could, he realised, be certain of salvation. This certainty that he was saved was the ‘distinctively new note in Luther’s theology’ (p. 70) and would become known by the catchphrase ‘salvation by faith alone’. Luther’s own perception of this shift in his life cannot be dated to the 95 theses, which did not touch upon this certainty. Rather, these ideas started materialising during the early months of 1518, in his instructions on confession and his sermon on preparation for communion.

The gradual development of Luther’s thinking is ascribed to the exchanges with other thinkers as much as to close reading of the Bible. In fact, Rex points out that Erasmus’s new Bible translation did not have as big an impact on Luther’s reconsiderations as did the Vulgate in the new medium of print. This new medium provided scholars with all the books of the Bible together, the commentary accompanying the Latin text handily available, and, most importantly, indexes which enabled cross-referencing. These innovations, in particular the indices, not only helped Luther, but also his readers in studying the Bible creatively and interconnectedly, and allowed scholars to trace back the steps of others’ arguments with the help of the reference tools. It was not the new translation, but the change of medium which was crucial in Luther’s intellectual development and in the reception of his teaching. Similarly, breaking with scholastic tradition of debating purely on memory, Luther brought his recently printed Resolution on Proposition XIII to the debate with Johann Eck at Leipzig in 1519. This put him on a stronger footing and changed his terms of engagement from then on. The confidentiality of closed scholarly debates was no longer guaranteed, nor desired. Once more, the tools of their disputations were instrumental in Luther’s articulation of his teachings.

Disputations, either in person or in writing, moved Luther to break new ground and express revolutionising ideas. Gradually, exchanges between Luther and his challengers moved from conversation to confrontation. In the process, the stakes were raised. ‘Luther was never a man to fold, but would always raise again’ (p. 91). Rex agrees with Erasmus who regretted the escalation of the debate through the fierceness of the responses. The debates shaped Luther’s thinking and his increasing intransigence, in the process, his divisiveness made its mark on the scholarly landscape. In an enticing turn of phrase, Rex states that the aftermath of Luther’s debate with Johann Eck about the primacy of the Pope at Leipzig ‘was the matrix in which humanist support for Martin Luther took firmer shape’ (p. 130). One feels that perhaps Rex has taken this humanist backdrop to the story too much for granted. This seems a missed opportunity for a study which so brilliantly introduces the otherwise complex ideas to a wider audience. Readers would perhaps have benefitted from greater contextualization. For instance, Rex points out that onlookers saw Luther’s disputes with various scholars as part of the wider confrontations which were taking place, in particular those between Desiderius Erasmus and Johann Reuchlin, scholar of Greek and Hebrew. But what those disputes entailed and what the implications of the associations were, we are left to look up ourselves. Tying those instances together and giving some more detail would have strengthened Rex’s exploration of the complexity of Luther as both a man of his time and innovator. But perhaps that is a result of Rex’s deliberate decision to keep wider reading beyond Luther’s own writing at a minimum, in order to give Luther’s words a fresh reading without unnecessary baggage.

Based on rather convoluted writings of Luther, Rex excels in creating a highly accessible study. Not only has he rendered complex theological arguments into understandable prose, he managed to make reading them very enjoyable. He has a pleasant turn of phrase which does not distract from seriousness and studiousness of the book, but is a credit to the playfulness of many humanist writings. Rex seems to take some pleasure in hinting at Luther’s combative persona: ‘Luther loved his enemies. He rejoiced in his hatreds and savoured them, rolling them around his mouth like some fine vintage’ (p. 215). Rex’s determined preference for strict history of ideas over more fashionable cultural and social history should not make a wider public hesitant to open the covers of this work. The Making of Martin Luther deserves a very wide audience who will enjoy gaining deeper insights into the thought processes of a man who, 500 years after possibly not nailing a sheet of academic thoughts on a door, inspired a year of creative and intellectual engagement with the Reformation on a broad scale.