Reading Time: 7 mins

New Zwingli Biography Reveals Differences with Luther

Reading Time: 7 mins

Zwingli the Pastor provides an excellent introduction to the Swiss reformer’s life and work, focusing on Zwingli’s philosophy of church reform, biographical details, and mode of exegesis.

When I saw that Dr. Stephen Brett Eccher, Associate Professor of Church History and Reformation Studies at Southeastern Baptist Theological Seminary was publishing a new book about Huldrych Zwingli, I promptly surrendered the necessary coinage to procure a copy of Zwingli the Pastor: A Life in Conflict (Lexham Press, 2024). After all, I am a Reformation nerd of increasingly epic proportions, but my knowledge of events in Zurich is somewhat limited. 

I was aware that he had once eaten a sausage during Lent and drowned Anabaptists. I had a reasonable sense of the position Zwingli had taken on the Lord’s Supper at the Marburg Colloquy in 1529, and I knew he influenced the trajectory of Reformed theology. However, that hardly seemed like a well-rounded portrait of such an influential person.

When I finally cracked open my copy of Zwingli the Pastor, I was repeatedly reminded of the Swiss reformer’s differences with Martin Luther. This was not the only theme in the book; Eccher also spends substantial time on areas of relative agreement, such as the doctrine of predestination. But perhaps because I have spent the last few years focusing on Lutheran theology, the areas of divergence were most striking. Below are the five main differences I observed from Eccher’s work: 

Difference #1: Humanism

The initial difference between Zwingli and Luther came early in their lives, before either made an evangelical breakthrough. Luther received a relatively standard late medieval education at the University of Erfurt, whereas Zwingli was heavily exposed to the nascent humanist movement at the University of Basel.

Humanists were known for their study of classical sources in the original languages, including the biblical text. As Eccher notes, “The humanist yearned to experience the past as a means of self-realization or finding one’s own potential as a person. An equation of virtue was constructed: ‘good letters lead, under God’s guidance, to good men’” (p. 7).

While Luther took advantage of some of the tools of biblical humanism, he was not a full humanist at heart, as seen in Zwingli’s more positive reaction to humanist stalwart Desiderius Erasmus. “Through Erasmus, Zwingli believed that one could meet Christ in the text of the Holy Writ. To encounter Jesus in the Bible was to be transformed by Him” (p. 25).

Studying classical sources brought Zwingli in contact with ancient philosophies, which proved crucial to his theological development. “Swimming alongside others in the waters of humanism is also how he encountered Florentine Neoplatonism, a movement that elevated the place of the spiritual over the material,” Eccher writes (p. 5). This would have a decisive impact on Zwingli’s later understanding of the Eucharist.

Humanism also affected Zwingli’s interpretation of the Bible. “As a humanist, Zwingli held the pursuit of the natural or plain sense of the text as one of the chief principles driving his exegesis. Such an approach meant looking for the Bible’s inner spiritual instructions as opposed to a rigid surface literalism” (p. 181).

Zwingli believed one must be skilled in the original Greek to grasp the full meaning of a text. In contrast, Luther made use of the Greek text, but had greater faith in the ability of the common person to understand the plain sense of Scripture, even in translation. The difference was often subtle, but it proved crucial.

Difference #2: Church and Society

Both Zwingli and Luther “desired an ordered Reformation, one free from social unrest and religious radicalism.” (p. 66) Neither favored the kind of societal restructuring promoted by Anabaptists or the violence of iconoclastic outbreaks.

Yet Zwingli held a more transformationalist view of the Christian life, as Eccher explains. “The Reformer believed salvation through Christ alone was the hope of humanity. He also thought the gospel was key to establishing the Christian society he longed for Zurich to become” (p. 86). Not only the justification of the sinner, but the improvement of society was dear to Zwingli’s heart. 

“A concern to craft argumentative forms that directed people toward besserung (“moral improvement”) and spiritual renewal characterized the movement. As individuals drew closer to God through the preached Word, becoming active participants in society, a residual collective gain for the Christian community was realized” (p. 43).

Zwingli did make a clear distinction between human and divine righteousness, as Eccher explains. “These ethical and moral guardrails are for the safety and good of society, though obedience to them does not grant one access to God’s divine righteousness” (p. 41). But the focus on creating an ideal Christian society in Zurich went beyond anything attempted in Wittenberg. 

Luther certainly wished to see a reduction of sin among his congregants and an increase in sanctification, but he was convinced they would always be simul iustus et peccator: simultaneously just and sinful. This led him to be somewhat wary of moral improvement drives, which could unintentionally place believers back under the law.

Difference #3: A Covenantal Theory of Worship

Another distinctive of Zwingli’s theology was his emphasis on the covenantal nature of the biblical narrative. “Prior to the mid-1520s, the preacher had already begun speaking in covenantal terms. However, from 1525 onward, he did so based on a strong connection between the Old and New Testaments, which also interweaved the old and new covenants” (p. 44).

Whereas Luther tended to emphasize the law/gospel distinction as the key to interpreting Scripture, Zwingli began the Reformed tendency of framing the events within Scripture in covenantal terms. He believed the Church was “a contemporary representation of Israel,” (p. 45) and wished to create a set apart community in Zurich. As the Old Testament prophets had condemned idolatry, so Zwingli used the language of idolatry to describe deviations from God’s Word. “For Zwingli, only God’s clear commands would suffice when determining liturgical norms” (p. 70).

This identification with Old Testament Israel had profound ramifications for worship. “To avoid idolatry, the Zurich churches removed images from their buildings, silenced organs, and whitewashed walls previously adorned with religious renderings” (p. 49). It even fueled Zwingli’s criticisms of Swiss mercenary fighting. “Idolatry was inherent in the accords made with foreign nations” (p. 117).

Covenant theology also provided a justification for Zwingli’s theology of baptism. He argued that the sign of the covenant had “shifted from circumcision to baptism. For Zwingli, ‘baptism is an external covenant symbol that all who are in the covenant receive without exception.’ Still, covenant continuity was key” (p. 44).

Viewing baptism as the new circumcision caused Zwingli to reject Luther’s understanding of baptismal regeneration: the idea that God performs the work in baptism rather than humans. Instead, “Zwingli was adamant that the water of baptism could not change the soul. Only the Spirit of God through the Word of God might usher in an internal disposition of piety. Instead, baptism placed the individual in the covenant community and set them on a redemptive pathway” (p. 177).

Difference #4: The Eucharistic Controversy

The showdown between Zwingli and Luther over the nature of the Eucharist has achieved legendary status. At Marburg in 1529, they debated the matter, with Luther always returning to a single word: is. When Christ said, “This is my body,” Luther believed he meant it literally.

Zwingli’s understanding of the Lord’s Supper was shaped by his humanist instincts. He knew the Latin word sacramentum originally referred to a military oath or pledge. Thus, the purpose of the Lord’s Supper was for the congregants to pledge and remember (p. 175). “Rather than seeing God as doing something for or to the communicant observing the meal, he highlighted the actions of the Swiss people” (p. 178)

In the words of institution, “This is my body. Do this in remembrance of me,” Luther focused on the first sentence and Zwingli the second. St. Augustine had taught that the sacraments functioned “ex opere operato, based on the act of observance, and detached from a divinely gifted faith” (p. 170). Zwingli rejected this and taught that “the recipient’s faith, not the independent sacramental actions of the elements, was what generated assurance in the believer.” (p. 180) Zwingli ultimately went further than Luther in stating that not all who are baptized are made regenerate and not all who receive the communion elements receive Christ’s body and blood.

Here Zwingli’s humanism was on full display. “The humanistic focus on the internal aspect of a person’s renewal guided Zwingli’s exegesis…Only an inner renewal by God’s Spirit, not external religious actions or rites undertaken by human hands, could change a person” (p. 168).

The upshot of this was that, “By November 1524, Zwingli argued for the first time that the word ‘is’ from Matthew 26 and Luke 22 should be understood to mean ‘signifies’ or ‘represents.’” (p. 174) Zwingli’s understanding of the original Greek text and historical literary tropes led him to this interpretation. He “rejected the notion that anything in our world, or even the Divine nature itself, could shift in essence or ontology” (p. 168), and furthermore held that “human acts cannot bind or force God to respond in certain ways according to necessary causation” (p. 170). Luther could not have been more utterly opposed.

“For the Wittenberg Reformer, Zwingli’s clever humanistic word games veiled the promise Christ made to his disciples regarding His presence in the elements…He concluded, ‘We condemn and damn alloeosis [the literary trope to which Zwingli appealed for his view] right down to hell as the devil’s own inspiration.’ For Luther, to follow Zwingli was to believe Satan and to reject the promises of God.” (p. 189)

In their meeting at Marburg, Luther continually referred to the plain meaning of the text, insisting that Christ had promised to give himself to the believer in the Supper. As always, Luther saw the sacraments as actions of God rather than man. One exchange is particularly revealing.

“As Zwingli referenced the Greek New Testament to defend his interpretation, Luther interrupted, ‘Read German or Latin, not Greek.’ Zwingli quickly responded, clarifying that he had been immersed in the original Greek text for years, admittedly having only read the Latin translation once” (p. 193).

It was in their understanding of the Eucharist that Zwingli and Luther’s different educational backgrounds created the greatest doctrinal fissure.

Difference #5: Law and Gospel

Zwingli also defined the gospel differently from Luther. “His articulation of the gospel focused on the community’s reconciled relationship with God and a subsequent obedience to His commands, as opposed to Luther’s emphasis on an individual’s justification” (p. 104). This meant that, “For Zwingli, the gospel was never merely appropriated by individuals internally but always shown forth externally into and through society” (p. 101).

While Zwingli did see salvation as entirely a work of God based on the righteousness of Christ and working of the Holy Spirit,

“Zwingli did not bifurcate the external work of God via divine declarations (justification) from the ongoing growth of the believer in Christlikeness (sanctification). He saw these two salvific components working together symbiotically in one gospel reality…Therefore, Jesus’s righteousness was ‘the initial and continuing source of a life like Christ’s.’ This meant Christ’s righteousness was both imputed and imparted. To belong to Christ in a salvific sense was to be like Christ in moral terms” (p. 107).

This led Zwingli to include things within “the gospel” which Luther would have excluded. The Swiss reformer once said, “I call everything ‘gospel’ which God opens to human beings and demands of them…For whenever God shows his will to people, it delights those who love God and thus it is to them certain and good news” (p. 107). The result was that, “Zwingli’s soteriology may perhaps be best framed in terms of a gospel/law symmetry, as opposed to Luther’s famous law/gospel dichotomy” (p. 107).


Zwingli the Pastor provides an excellent introduction to the Swiss reformer’s life and work, focusing on Zwingli’s philosophy of church reform, biographical details, and mode of exegesis. It presents a man of strengths and weaknesses attempting to do God’s work in a chaotic world. The split with Luther at Marburg was the result of local circumstances, educational differences, and two equally fiery but nevertheless different personalities. I recommend the book for anyone seeking to understand the Reformation better.