Below is an excerpt from Chapter 3 of The Oxford Handbook of Reformed Theology , by Carl Trueman. Dr. Trueman received his PhD in Church History from the University of Aberdeen. He is Professor of Biblical and Religious Studies at Grove City College.

The Origins and Development of the Lutheran/Reformed Confessional Division
The origins of the major confessional division between Luther and the Reformed lie in the debates about the Lord’s Supper between Martin Luther and Huldrych Zwingli in the 1520s. Luther’s eucharistic theology was rooted in a number of personal convictions which drew their intensity because of aspects of his personal autobiography. His first Mass had been a traumatic experience, given the fact that he, a sinful priest, had to make and to handle God. Further, he was convinced that God only gave himself as gracious to his people in the flesh of Christ. Thus, for the Eucharist to be Gospel, the flesh of Christ had to be present (Jensen 2014).
To these positive impulses towards the Real Presence, we should add Luther’s negative encounters with symbolic views of the elements. While Luther was absent in the
Wartburg in 1521–2, his colleague Andreas Bodenstein von Karlstadt had implemented iconoclastic reforms through student riots and had hosted a radical spiritualist group, the Zwickau Prophets. He also advocated a symbolic view of the Eucharist. This fixed in Luther’s imagination a connection between political radicalism, social unrest, and spiritual/symbolic understandings of the Eucharist (Lohse 1999, 170).
Zwingli, by contrast, was trained as an Erasmian, his autobiography lacks all signs of the inner existential struggle, and his theology was rooted much more in the notion of a general reform of church, state, and doctrine in light of scripture than in the more specific Christological and soteriological concerns of Luther. He was very influenced by the insight of Cornelis Hoen that the word ‘is’ in ‘This is my body’ could mean ‘symbolizes’, and developed a strongly symbolic view of the sacrament. For him, the Supper was more of a horizontal event which publicly bound together Christians by mutual oath. The metaphysics of presence were at best irrelevant to his theology (Potter 1976: 326; Stephens 1986: 232–4).
The clash with Zwingli, therefore, needs to be understood against the broader background of Luther’s own personal struggles and also of his clash with the radicals. After 1522, he always associated talk of a symbolic Eucharist with spiritualist excess. Zwingli, as advocate of a symbolic view, appeared to Luther merely as the polite, well-educated face of fanaticism.
The pamphlet war between Lutheran and Zwingli and their cohorts came to a climax at the Marburg Colloquy in 1529. The Luther and Reformed delegates reached agreement on fourteen and a half of fifteen points. The key area of disagreement was that of the Real Presence. Luther and his followers maintained an objective presence of the whole Christ in the bread and wine, while the Reformed maintained a symbolic, and at best spiritual, presence. The difference is more than merely a sacramental point, however. It is rooted in a fundamentally different understanding of the communication of attributes in the person of Jesus Christ. Lutherans maintained that the communication between the divine and human took place directly between the natures. The Reformed believed the communication was indirect, to the person (Lohse 1999: 174–5, 231; Arnold 2014: 282–3; Stephens 1986: 112–17).
This point became the primary issue of confessional divergence between Lutherans and Reformed. While there were other points where the two traditions differed (for
example, in their attitudes to physical representations of Christ), the Christological issue was primary, rooted in the difference over the communication of attributes.
Lutheran orthodoxy developed an elaborate taxonomy so as to be able to discuss the communication of attributes in a very subtle and precise way. The Reformed, holding to the basic, catholic understanding of the Incarnation and to a view of the Lord’s Supper, which denied Christ’s local presence according to his human nature, had no need for such.
The Reformed, however, were not monochrome on the issue of how Christ was connected to the Lord’s Supper. Zurich tended to hold to a more strictly symbolic view,
while Geneva, under John Calvin (1509–64), moved to an emphasis not so much on the symbolism as upon the spiritual eating of Christ which takes place by faith, as set
forth by Calvin in his 1559 Institutes, book 4, chapter 17. That there was no substantial Christological difference between these two approaches is reflected by the fact that
both Geneva and Zurich signed a joint understanding on the Eucharist, the Consensus Tigurinus of 1549. But the role of the sacrament in the tradition of Calvin was much
richer, not merely a symbol of grace but a sign and a seal with real spiritual and existential significance. Indeed, the background to the Consensus indicated some misgivings on Calvin’s part (Gordon 2009: 179–80).
The Eucharist also played a role in more positive attempts at Lutheran–Reformed ecumenism. In 1540, Melanchthon modified the Augsburg Confession (1530) in a manner which made the statement about the Real Presence somewhat more ambiguous. It was this version of the Confession (the variata) to which Calvin was able to subscribe (Gordon 2009: 236). It was also this version of the Confession that played a part in the post-1546 division within Lutheranism between Philippists (followers of Melanchthon) and the Gnesio-Lutherans. The former favoured the variata, the latter the original 1530 text, the invariata. This shaped the dynamics of the battle for Luther’s legacy, and indeed the ongoing politics of the relationship between Lutheran and Reformed (Kolb 1996: 1–17).
Thus, this division within Lutheranism was of immense significance to the development of confessional Reformed theology in the sixteenth century. In the early 1560s, the Elector Palatine, Frederick III, converted from Philippist Lutheranism to the Reformed faith and commissioned a catechism. The result—the Heidelberg Catechism (1563)—was intended in part as an ecumenical document to which Reformed and Philippists could subscribe, while excluding the more hardline Gnesios. Thus, the Catechism contains no explicit teaching on predestination (a point which would have alienated the Philippists) and yet does have a significant number of questions (7 out of 129) detailing the ascension and session of Christ (thus emphasizing a Reformed/Phillipist as opposed to a Gnesio Christological context for understanding Christ’s presence in the Eucharist) (Bierma 2013: 63–4). The Heidelberg Catechism was to become a standard confessional document of the continental Reformed churches. For example, it was given normative confessional status at the Synod of Dordt (1618) (Gunnoe 2005).
From The Oxford Handbook of Reformed Theology edited by Michael Allen and Scott R. Swain. Copyright © 2020 by Michael Allen and Scott R. Swain and published by Oxford University Press. All rights reserved.