Ad Fontes: How the Bible Shaped a Movement

G. Sujin Pak on the significance of theology for the Protestant reformers

Martin Luther’s reformation was theological through and through. At its very heart were questions of theology. To claim this is not to deny or undervalue the important implications his reforming efforts had for matters of economics, social life, and politics; it is to claim that one will not fully grasp the core program of Luther’s reformation in particular—as well as the multiple reformations of the sixteenth century (i.e., Swiss Reformed, Calvinist, Anabaptist, and Catholic)—without the recognition of its profound theological claims and commitments. “Theology” by definition is the study of the nature of God and religious belief. The foremost concerns of the leading Protestant reformers—Martin Luther, Huldrych Zwingli, and John Calvin—were precisely to correct what they believed to be mistaken understandings of the nature of God, the nature of humanity, and the nature of faith. These concerns converged into a larger, pressing need to rectify the various conceptions of justification—how one is saved—in their time. Yet, as we will see, their assertion that salvation is entirely the work of God through God’s gift of faith, in which human works make no contribution, had direct implications for views of authority, definitions of “church,” and Christian worship practices.

 Right Knowledge of God & Right Knowledge of Self: Justification by Faith Alone

Toward the end of his life, Martin Luther described his “reformation breakthrough” as the profound discovery that rather than God being a righteous God who demanded perfect righteousness from the human subject and who was always ready to punish the human for falling short, God is in fact a merciful and loving God who provides the very righteousness necessary to the human as a gift. Looking back on his early years, Luther wrote in his 1545 preface to his Latin writings, “I began to understand that the righteousness of God is that by which the righteous lives by a gift of God, namely by faith.” For Luther, this involved first and foremost aligning conceptions of God, the human, and faith more closely with the teachings of scripture. As a monk, Luther had primarily been trained in the teachings of the leading nominalist theologians of his day: Gabriel Biel and William Ockham. Gabriel Biel is perhaps best known for the motto “facere quod in se est” (“to do what is in one”)—the idea that one should do what lies in one and then God will do the rest. The prevailing tendency in this motto was to emphasize the role of the human “to do what is in” her—that is, to emphasize the role of human works in salvation. To be clear, among those theologically versed, the matter was much more complicated, for Biel’s conception of “what is in one” entailed not merely the positive role of human works but the very definition of grace as God leaving the human will intact enough after the Fall (into sin) to be able to make a movement (however small) toward the good, and then God would provide additional grace to make up the gap. Yet, such theological subtleties often get lost in everyday practice and understanding, and such was the case in Luther’s day. Ultimately, argued Luther, people were being taught that they were saved by their own efforts and good works. He criticized the church of his day for promoting a variety of human works as the means by which one’s salvation was secured, such as the following: buying an indulgence (i.e., a grant for remission of the temporal punishment of sin to gain a loved one a certain number of years out of purgatory), giving of land and monetary gifts to the church, dedicating a son to the priesthood, or going on pilgrimage to a holy site. On top of this, each of the three steps in the sacrament of penance—confession, contrition, and satisfaction—ostensibly accentuated human effort: Did the sinner confess thoroughly enough? Was the sinner sufficiently contrite? What good works must the sinner do to make satisfaction for his sins?

Luther argued that as a consequence of such practices, Christians lived with a “terrified conscience,” a wrong view of God, and a wrong view of self. Christians wrongly viewed God as a punitive God whom they must appease by their good works. They also wrongly viewed themselves as capable of righteousness and good works in and of their own ability. Rather, insisted Luther, true righteousness is God’s work alone offered in Christ through the gift of faith. Instead of constantly striving to do enough, the powerful message of the Gospel is the freedom it offers—the freedom of realizing that no amount of human striving can adequately obtain salvation, the freedom of realizing that salvation is by God’s gracious activity alone offered in Christ through faith as a gift of God. Luther clarified that God gave the law revealed in scripture to unmask human sinfulness by demonstrating that humans are incapable of keeping the law perfectly; they cannot keep all of the law nor can they do so at all times. Humans will always fall short, and that is precisely the point! In the recognition of human inadequacy, the necessity of Christ takes center stage. Christ is the God-Human who is the only one capable of fulfilling the law perfectly. Christ exchanges his true and pure righteousness for human sinfulness, thereby clothing the human in Christ’s own righteousness. Through this gift of righteousness and faith, the human becomes a new creation in Christ, freed and able to do good works not as something that contributes to his or her salvation, but as the necessary, true, and right response and fruit of the salvation given (gifted) in Christ. In this way, Luther maintained that works belong properly to the neighbor as an expression of Christian love. For Luther, not only a right conception of salvation was at stake; the very necessity of Christ was at stake, for if one can be saved by good works, why would God need to send Christ at all?

I have focused upon Luther thus far because of his initial, leading role. Suffice it to say that on this matter of a right understanding of salvation as entirely the gift of God through Christ—i.e., justification by faith alone—Huldrych Zwingli and John Calvin also asserted these same points as indispensable correctives central to their own reforming work. It may sound strange to our ears today that a right understanding of salvation would evoke such urgency. Here, Bruce Gordon’s reminder in his introduction to this forum bears repeating: the roots of the Protestant reformations are found in the medieval world. The Protestant reformers still lived in a medieval world and mindset where wrong teachings concerning Christian faith (heresies) could not be tolerated, lest a single soul be lost on account of such wrong teachings. The whole work and purpose of the Christian church on earth could be boiled down to its call to rightly teach and guide its people on the proper path of salvation. According to Luther, Zwingli, Calvin, and other sixteenth-century reformers, the church of their day—indeed, the church for several centuries—has been increasingly failing at this crucial task.

Authority, Scripture, and the Church

This view leads directly to a second set of converging theological concerns at the heart of the Protestant reformations: conceptions of authority, the centrality of scripture, and the church’s proper identity and vocation. Luther, Zwingli, and Calvin each insisted that their corrections to the Roman Catholic Church’s teachings concerning salvation, faith, and works (as well as understandings of human nature and the character of God) brought Christian faith and practice back to the teachings of scripture, in which the Bible is the primary—if not sole—authority for the Christian life. The Protestant reformers rigorously challenged prevailing views of the authority of the church and its relationship to scripture. The Catholic Church of their day upheld a kind of symbiotic relationship between the authority of the ordained leadership of the church (i.e., priesthood) and the authority of scripture. According to Catholic belief, both scripture and the priesthood are ordained by God and granted authority in guiding the life of the faithful. More specifically, Catholics maintained that scripture is obscure in many places. On account of this, God granted the gift of the priesthood, through whom God provided a specially designated human institution to guide the church in its beliefs and practices—for the priest by virtue of the sacrament of ordination is set apart as God’s vessel to shepherd the church. Consequently, Catholics soundly affirmed the authority of scripture, but maintained that God equally provided an ordained, authoritative body (the priesthood) to lead the church in interpreting and applying scripture and in matters not explicitly addressed in scripture.

Scripture’s Prime Authority and Perspicuity

Luther, Calvin, and Zwingli pointed out, however, that much of the Roman Catholic priesthood was not only teaching their people wrongly (i.e., contrary to scripture); they were blighted by numerous moral corruptions, including economic exploitation, avarice, and sexual improprieties. “What kind of authority can and should such a morally corrupt and theologically unsound priesthood have?” asked the Protestant reformers. On the contrary, they argued that scripture is the prime authority for Christian life to which all leadership of the church should submit. Luther, Zwingli, and Calvin insisted that God’s Word is prior to the church and, thus, as Luther clarified in “On the Misuse of the Mass” (1521), “The church does not constitute [God’s] Word but is constituted by the Word.” Calvin similarly exclaimed in his Institutes, “But a most pernicious error widely prevails that scripture has only so much weight as is conceded to it by the consent of the church—as if the eternal and inviolable truth of God depended upon human decisions!” Thus, as part of their assertion of its prime authority, the Protestant reformers maintained that scripture is self-authenticating and self-interpreting, by which they aimed to place scripture above the reach of any human endeavor to claim its authoritative, final interpretation, including the ordained leadership of the church. On the contrary, the true interpreter of scripture is the Holy Spirit, who is its very author. In On the Bondage of the Will Luther therefore maintained against his Catholic opponent Erasmus’s assertion of free will, “No one perceives one iota of what is said in the scriptures unless one has the Spirit of God.” Calvin likewise explained in the Institutes that the Word of God “cannot penetrate into our minds unless the Spirit, as the inner teacher, through illumination makes entry for it.” Indeed, given the human’s bondage to sin, the Holy Spirit must be the primary actor in any faithful interpretation of scripture. Thus, a parallel might be drawn between the reformers’ insistence upon God as the sole actor in justification (justification by faith alone) and the Holy Spirit as the essential actor in scripture’s interpretation—both are rooted in the Protestant reformers’ convictions of human depravity and their visions of God as the initiator of all things pertaining to salvation.

If scripture is the prime authority for all Christians and the life of the church, in which scripture shapes and guides all other authorities as subsumed under it, then scripture must be clear. This is precisely what Luther, Zwingli, and Calvin (as well as many Anabaptists) argued. But, it is important to understand just what the Protestant reformers meant by this. They did not mean that every passage of scripture is clear, nor did they mean that it is clear to everyone. Rather, scripture is only clear to those who have been justified by faith alone—to those who have been given the necessary gifts of faith and the Holy Spirit. Moreover, the Protestant reformers recognized that there are many obscure passages in scripture; yet, they maintained that the central subject matter of scripture is clear. First and foremost, all of scripture points to Christ. Christ is its clear subject matter (to those who have faith and the Holy Spirit). More specifically, the clear subject matter is the overarching narrative that reveals scripture’s central soteriological purposes precisely centered in Christ. In his 1538 exposition of Psalm 51, Luther maintained that all of scripture points to “the human guilty of sin and condemned and God the Justifier and Savior of the human sinner.” In response to Erasmus’s claims that the human will is free and scripture is obscure, in Bondage of the Will Luther asserted the essential tenets of scripture’s clarity: that “Christ the Son of God has been made man, that God is three in one, that Christ suffered for us and is to reign eternally.” In other words, the clear subject matter of scripture is its revelation of the proper path of salvation (i.e., justification by faith alone), which includes clear teachings concerning right knowledge of God (as Justifier, Savior, Trinity), the centrality of Christ (incarnation, passion, and resurrection), and right knowledge of self (as sinner in need of Christ).

Re-Envisioning the Church’s Identity and Vocation

Insisting upon the prime authority of scripture not only led the Protestant reformers to recast the proper place of church authority, it led them to re-envision the very identity and vocation of the church exactly in terms of its right relationship to God’s Word. For example, contrary to Catholic Cardinal Jacopo Sadoleto’s definition of the Christian church as “a society of saints spread over the whole world, existing in all ages, yet bound together by the one doctrine and one Spirit of Christ,” Calvin countered that such a definition lacks one of the most crucial elements: that the church is that community of saints who hear and obey the Word of God. “What comes of the Word of the Lord, that clearest of all marks, and which the Lord himself, in pointing out the church, so often recommends to us?” asks Calvin in his reply to Sadoleto. By defining the church as that community who hears and obeys God’s Word, the proclamation of God’s Word (preaching) took center stage in the worship life of Protestant churches. In their aim to bring the definition of church and its vocation in closer alignment with the teachings of scripture, the Protestant reformers proffered the New Testament model of the church as the biblical prototype for emulation. Specifically, this meant that the leadership of the church should adhere to the church offices demarcated in the New Testament—such as the offices of pastor, teacher, elder, and deacon. Though the Protestant reformers did not agree on exactly which offices are biblical (for there was particular disagreement on the office of bishop), they unanimously viewed the papal office as unbiblical and, thus, soundly rejected papal authority. Moreover, the reformers argued that the biblical text clearly pointed to a married clergy (e.g., I Timothy 3:2), thereby repudiating a centuries-old tradition of celibacy as a requirement for priestly ordination.

As for vocation, the Protestant reformers rejected the customary separation between the “spiritual estate” and the “temporal estate,” in which only those who are ordained priests or who have set apart their lives for God as monks and nuns are part of the “spiritual estate” and have a “vocation” from God. On the contrary, the Protestant reformers insisted that all Christians, by virtue of their baptism, are called to bear witness to God’s Word, to proclaim God’s Word, to read scripture, and to rebuke wrongdoing and wrong teaching insofar as they depart from God’s Word revealed in scripture—thereby exactly defining each Christian and the church as a whole in the very acts of hearing and obeying God’s Word. Consequently, not only priests, monks and nuns are “spiritual,” but all Christians are spiritual and have a vocation to hear and obey scripture. Involved in this reconceptualization of who the church is and what the church does through centrally defining it by its relationship to God’s Word, the Protestant reformers radically redefined “priesthood.” The reformers drew a distinction between priesthood and ministerial offices: all Christians are priests; some Christians possess the call and gifts to hold a ministerial office. Those holding a ministerial office submit to scripture’s prime authority and wield authority only insofar as they rightly proclaim and follow scripture; they may be married; and ordination is an affirmation of a calling, not a sacrament. That is, the Protestant reformers no longer viewed ordination as one of the sacraments of the church. The radical nature of this change cannot be overstated. In a Catholic sacramental view of priestly ordination, the priest becomes something other; he is set apart to be a very means of God’s grace to the people, a vessel and mediator of God’s grace, in which it is promised that God’s grace will be mediated regardless of the priest’s holiness or abilities (for that is the very definition of a sacrament). Alternatively, the Protestant reformers presented ministerial offices as something to which one is called by the larger community and for which one should have gifts as discerned by the community. Consequently, authority is not automatically attached to the office (as something ontological due to its sacramental character); rather, authority is recognized only when there is right adherence to and implementation of scripture’s authority.

Scripture, Worship, and the Sacraments

Redefining the church’s authority, identity, and vocation in scriptural terms and under the prime authority of the Bible set in motion a reevaluation of the church’s worship practices also according to the measure of scripture. This development leads to a third set of converging theological concerns that further illuminates the crucial role of theology in the sixteenth-century Protestant reformations: the promotion of a scriptural vision of worship expressed in the centrality of preaching, Protestant iconoclasm, and assertion of only two biblical sacraments. For many centuries prior to the rise of Protestant churches, the celebration of Eucharist (the Catholic Mass) was the centerpiece of Christian worship. By defining the church as the community of saints who hear and obey God’s Word, the proclamation of God’s Word took precedence in the worship life of early Protestant communities. The sermon—the preached Word of God—replaced the Mass as the heart of Christian worship. Moreover, the Protestant reformers launched a number of objections against Catholic worship forms and practices, starting with the Mass. Luther, Zwingli, Karlstadt, and Calvin, among many others, argued that Roman Catholics had made the Mass into a human work, as if it were something humans offered (or sacrificed) to God instead of focusing on the primacy of God’s activity, in which God promises and enacts grace in the sacrament. Furthermore, they rebuked the veneration of the consecrated Host as an idolatrous practice, refuted the doctrine of transubstantiation (as unbiblical), and contested the withholding of the cup from the laity (as unbiblical). The Protestant reformers argued that the Eucharistic liturgy should be said in the vernacular, so that the whole community may more fully understand and participate, and they insisted that there should be no celebration of the Eucharist without the preaching of the Word, for Word and Sacrament belong inextricably together.

The Protestant reformers further aimed to rectify a number of the worship practices of their day. They rejected the use of relics and icons as idolatrous, citing the first of the Ten Commandments and the exhortations of the Old Testament Prophets. Some reformers (such as Calvin, as well as the Anabaptists) argued that anything that is not directly described or prescribed in scripture should have no place in the worship life of the church, so that, for example, some spurned the use of organs and other musical instruments in worship. Such views lead to the eruption of sometimes riotous iconoclasm (the destruction of paintings, sculptures, relics, and organs) in regions where Protestant views were gaining a foothold. Additionally, the Protestant reformers condemned the belief in purgatory as unbiblical and thereby repudiated the practices of indulgences and prayers for the dead that accompanied it. Against various penitential practices that emphasized either the sole ability of the priest to forgive sins or the necessity of the sinner to demonstrate notable effort and good works to gain such forgiveness, the Protestant reformers asserted that one can confess one’s sins to anyone and anyone can proclaim the forgiveness offered because the actual granting of forgiveness belongs to God alone, who grants it freely (without works) to the truly repentant (as exemplified in James 5:16). At the core of these objections to many of the Roman Catholic worship practices of their day were three things: the desire to bring worship back into alignment with scripture’s clear teachings, the aim to place the focus of worship upon God and God’s activity rather than human activity or works, and the need to purify Christian worship from what the reformers viewed as idolatrous practices.

Holding the worship practices of their day up to the mirror of scripture animated the Protestant reformers to reevaluate the nature of a sacrament and reduce the number of the true, biblical sacraments of the church from seven to two. The Roman Catholic Church upheld seven sacraments, but the Protestant reformers argued that only two of these have a clear biblical basis and were instituted by Jesus Christ: baptism and Eucharist—the latter they preferred to call the “Lord’s Supper.” Luther, Zwingli, and Calvin agreed that a true sacrament must be clearly instituted by Christ. They also agreed that the primary actor in a sacrament is God, in which God either declares, signifies, or mediates God’s grace. Consequently, the preaching of God’s Word must always accompany the celebration of a sacrament, so that there is a clear communication of God’s promises. Yet the precise nature of what actually happens in the celebration of the sacrament becomes a point of contention among the Protestant reformers. Does the sacrament simply declare a grace already present spiritually? Do the elements of the sacrament signify the grace declared, or do the material elements of the sacrament both signify and actually mediate grace? The differences and harsh debates among the Protestant reformers concerning these questions became a matter upon which they could not agree and were unwilling to compromise. Why? Because precisely the nature of true faith, Christology, scripture’s authority, and the right practices of worship were at stake—that is, the key theological tenets upon which the various Protestant reforming movements were grounded in the first place. Citing the text that the “flesh profits nothing” (John 6:63), Zwingli argued that true faith could never trust in material things, which could only lead to various forms of idolatry. Consequently, Zwingli argued that the Lord’s Supper is a meal of remembrance of Christ’s death that commemorates and simply declares a grace already spiritually given directly to the believer. Luther, on the other hand, insisted that Christ’s words “this is my body” are true, literally, so that the sacrament does not merely declare grace; it mediates grace precisely through the material elements, for exactly a right understanding of Christ’s Incarnation was at stake. Of course grace can be mediated through material things, insisted Luther; otherwise, what is the Incarnation? Without belaboring the many theological subtleties in the Protestant reformers’ debates over the Lord’s Supper, the disputes boiled down to their conflicting claims of having the right Christ, the right understanding of faith, and the right enactment of scripture’s authority—all of which were for them non-negotiables.

A clear common thread in the three sets of converging theological concerns highlighted here—reassessment of teachings on justification, re-conceptions of church (its authority, identity, and vocation), and reevaluation of worship and the sacraments—is the appeal to bring each of these into better alignment with the teachings and prime authority of scripture. There were some followers among the early Protestant movements, however, who did not believe these movements went far enough. In response, several of these groups made an even more profound appeal to the sole authority of scripture. These groups, perhaps most notably the Anabaptists, proposed a radical vision of the church as a community guided by congregational rule and called to live holy lives set apart from the world in literal obedience to Christ’s teachings in scripture, which included a staunch rejection of any connection to the state, the taking of oaths, and use of the sword (the latter with a couple of tragic exceptions). In a manner, the Anabaptists took many of the key concerns of Luther, Zwingli, and Calvin and magnified them through a principle of sola scriptura. They asserted an even more literal imitation of the New Testament church as the true model of the church. Through a literal interpretation of scripture and a sola scriptura principle, they rejected the practice of infant baptism as a contrived tradition of the church that had no biblical basis and even more robustly repudiated any forms of worship that had no historical basis in the apostolic church described in the New Testament. They denied “sacraments” altogether in favor of a view of these as simply memorials: baptism as a public, voluntary vow of a commitment to Christ and the Lord’s Supper as a meal of fellowship that commemorated Christ’s death and resurrection, in which the concept of material things as a sign and means of grace (i.e., the definition of a sacrament) held no place at all.

Admittedly, the reform of the church’s worship practices and challenges to ecclesiastical structures and authority were not merely theological matters, for they bore deep political, social, and economic implications, incentives, and assumptions. Nonetheless, Carlos M. N. Eire remains correct in underscoring the crucial role of the theological convictions of the Protestant reformers—particularly those of justification by faith alone and the prime authority of scripture. Eire writes in his recent book Reformations: The Early Modern World, 1450-1650, “The two principles alone do not explain the whole of Luther’s theology, but it is impossible to understand Luther and the whole Protestant reformation without them.” Indeed, as I have argued, these two theological convictions not only undergirded re-conceptualizations of salvation and the church, they were the principles generative of new Protestant theologies, forms, and practices of worship.


G. Sujin Pak served as Associate Dean of Academic Programs at Duke Divinity School from 2012-15 and is a faculty member in the history of Christianity at Duke Divinity School since 2008. She specializes in the history of Christianity in late medieval and early modern Europe, in which her research focuses upon the theology of the Protestant reformers, the Protestant Reformation and the Jews, women and the Reformation, the history of biblical interpretation, and, more recently, views and uses of prophecy in the early modern era. She has published two books, one entitled The Judaizing Calvin: Sixteenth-Century Debates over the Messianic Psalms (Oxford University Press, 2010) and another forthcoming with Oxford entitled The Reformation of Prophecy: Early Modern Interpretations of the Prophet and Old Testament Prophecy. Pak has also written several articles in journals such as Church History, Reformation & Renaissance Review, Religions, Calvin Theological Journal, and Church History and Religious Culture.