The dispute over the real presence of the body and blood of Christ in the eucharist led to a permanent division between Luther's Wittenberg Reformation and Zwingli's Swiss Reformation. Landgrave Philip of Hesse's attempt to settle the differences at the Marburg Colloquy in 1529 was unsuccessful. But in the following years, after protracted negotiations, an agreement was reached between the Wittenbergers and the south-west German Protestants on the doctrine of the eucharist. In May 1536, a convention was held in Wittenberg, at the end of which the so-called Wittenberg Concord (Wittenberger Konkordie) was signed, enabling the South Germans to accept the Confessio Augustana and join the Schmalkaldic League.

The initiator of the efforts that led to the Wittenberg Concord was the Strasbourg reformer Martin Bucer. Since 1528 he had been developing a mediating view in the controversy over the eucharist, admitting the real external presence of Christ's body and blood, but denying that it was subject to human access and therefore rejecting the idea of its oral reception by both believers and the ungodly (‘manducatio oralis et impiorum’). At the end of September 1530, Bucer, who had attended the Diet of Augsburg, visited Luther at the Veste Coburg and was able to persuade him to enter into negotiations. Reinhardt's book examines in detail the course of the six-year negotiations from 1530 to the Wittenberg Concord Convention in 1536, with a special focus on Luther's role. He draws on some sources that have not been considered in this context so far, including passages from Luther's Table Talk, but above all he tries to understand the negotiations consistently as a dialogue and two-way communication process between Bucer and Luther, taking also in account, of course, the other participants. In doing so, he arrives at remarkable new results. For his book, a Berlin doctoral thesis, the Luther-Gesellschaft awarded Reinhardt the Martin Luther Prize for Young Scholars in 2018.

I cannot present Reinhardt's reconstructions of the various stages of the many years of negotiations in detail here and will limit myself to recording the most important results. Above all, it is now clear that Luther was by no means a mere observer of the Concord negotiations, but that he was the dominant actor throughout their duration. Quite naturally, he saw himself in the role of the judge before whom the opposing side had to justify their cause and who had the exclusive right to pronounce the final sentence. It was he who determined the procedure and the topics that were to be the subject of the discussions. Thus, the path to the Concord was essentially taken in the dialogue between Bucer and Luther. Reinhardt's study also sheds light on Luther's temporary break with Bucer and his withdrawal from the Concord negotiations in November 1531 which so far has seemed strangely unmotivated. As Reinhardt can show, the cause was Bucer's letter to Melanchthon of 24 October 1531, in which he reported Zwingli's death in the battle of Kappel and tried to dissuade the Wittenbergers from condemning Zwingli too harshly. Luther understood this plea as a commitment to Zwinglianism and as proof of Bucer's untrustworthiness and broke off contact. It was to Melanchthon's credit that he maintained contact with Bucer during this period and persuaded Luther to continue negotiations in September 1534; at the Kassel Colloquy in December 1534, Melanchthon negotiated alone with Bucer at the court of Philip of Hesse. For the rest, however, Melanchthon and the other actors, such as the princes of Hesse and Saxony, played only a subordinate role. However, Luther made a point of involving other theologians of the Wittenberg Reformation in the conclusion of the Concord.

Luther attached importance to the Wittenberg Concord as not only being an agreement on the doctrine of the eucharist, but as also including articles on baptism and the office of the keys. In fact, the question of the eucharist was still at the centre. Reinhardt points out that Luther did not really understand Bucer's position until the end. For him, the real presence of the body of Christ was directly and inevitably linked to its oral reception by both believers and ungodly communicants, so Bucer's view must have seemed at least inconsistent to him. But finally, Luther declared himself satisfied with the terminology agreed in the Wittenberg Concord. According to these, the bread was the body of Christ by virtue of a ‘sacramental union’ (‘unio sacramentalis’) and was received ‘together with’ (‘cum’) the bread by communicants, even by those who were ‘unworthy’ (‘manducatio indignorum’). Luther's conviction that the South Germans were now in total agreement with him about the presence of Christ's body in the eucharist was, of course, incorrect (unlike in the case of baptism and the keys). From Luther's point of view, the Concord he had signed was his expert opinion on the doctrine of the eucharist, which testified to the authentic notions the South Germans had expressed at the Wittenberg Convention and recognised these as the basis for a consistent doctrinal concordance.

With his careful and close-to-the-source study, Reinhardt has succeeded in comprehensively reconstructing the history of the Wittenberg Concord and the events of the Concord Convention of May 1536 and plausibly interpreting their dynamics and results. Last but not least, he can show that Luther had by no means lost his influence on developments in the Reformers’ camp in the 1530s, as some recent researchers have assumed. However, the Wittenberg Reformer had not yet spoken his last word in the dispute over the understanding of the eucharist. In his ‘Short Confession of the Holy Sacrament’ of 1544, he even implicitly distanced himself again from the Concord of 1536. The inclusion of the later years would have gone beyond the scope of the present volume. But it would be worthwhile and exciting now to also examine in detail the post-history of the Wittenberg Concord, its reception and ratification during the years 1536 to 1544 in the light of the insights gained by Reinhardt.