top of page
  • Sarah Mortimer

Separating the Two Swords

Sarah Mortimer on the Reformation and political thought

The theological revolution begun by Martin Luther in 1517 not only challenged the authority of the Catholic Church, it also overturned contemporary ideas about politics and government. Luther’s dramatic reinterpretation of the Christian faith led him to see earthly authorities in a new and unsettling way, casting doubt on their value within the divinely ordained order. His bold claims about the freedom and equality of Christians and their obligations to love their neighbors seemed to consign politics to the shadows, necessary only because so few of us are able to live truly Christian lives. Yet Luther’s followers found this position impossible to maintain. They came to see princes as crucial for the spread of the gospel and they wanted to encourage Protestants to involve themselves in civil and political life. Reconciling political participation and Lutheran theology was far from easy, however, and from the earliest years of the Reformation to the present day, Protestants have sought ways to understand the place and value of human authority. The answers generated by Luther’s heirs still shape our ways of thinking about politics – and the relationship between politics and Christian life.

Luther’s new theology had dramatic implications for political thought because it denied the sense of continuity between earthly and heavenly values so important to his contemporaries. Most sixteenth-century Catholics presented civil rulers in a positive light, part of God’s plan for his human creation and tasked with bringing about earthly peace and prosperity. But Luther cast the Christian condition as inherently paradoxical, a dialectic between sin and grace – and as a consequence he often suggested that worldly authority was nothing more than a way of managing sin. His theology left little space for politics conceived as a noble, even if inferior, endeavour in its own right. Instead, politics seemed to be a consequence of human corruption, fundamentally different from the community of true Christians united by grace. Although Luther saw himself as strengthening the authority of princes, protecting them from the Catholic efforts to encroach on their power, even his allies feared that he was having the opposite effect. Through the early modern period, Protestants sought to explain how Christian people could take on political commitments without sacrificing their theological principles, a complex task in a period of turmoil and religious warfare.


It was Luther’s understanding of the Christian life that gave rise to his earliest ideas about politics and earthly authority. For him, the Christian was justified by faith and yet remained sinful while on this earth; he or she was freed in Christ but bound to serve and obey in this fallen world. Men and woman were subject to God’s law, laid down in nature and in the Ten Commandments, but they were unable to fulfill it; only through grace and not through good works could they find favor with God. Christianity was not a system of new and superior ethical rules, as he believed the traditional Catholic position all too often implied. It was instead an attitude of love, a disposition of charity and service towards all fellow human beings. And yet for Luther laws and rules were still part of the Christian story; the gospel was different from the law but inseparable from it.

In his simplest formulations, political authority was part of the Christian paradox: it was necessary to curb the sinful tendencies which all humans displayed, but this necessity stood in tension with the gentle, spiritual rule of the heavenly kingdom. Viewed in this light, worldly rule seemed to be little more than a mechanism for dealing with depraved and corrupt human beings, indispensable but of little positive value, and certainly Luther sometimes presented politics in this way. In his short work On Secular Authority, Luther emphasized that the kingdom of the world existed primarily to restrain sinners – in contrast to spiritual authority – and that “care must be taken to keep these two governments apart.” At the same time, Luther also saw earthly authority as divinely ordained, given by God in order to prevent chaos and anarchy, and he pointed to the several scriptural verses that commanded Christians to obey their rulers. That obedience was due not only from laypeople but also from clergy, who – given Luther’s views on the priesthood of all believers – could stake no claim to any special status here on earth.

Although Luther insisted that the magistrate’s task was given to him by God, he set little store by earthly prosperity or success. Instead, Luther emphasized the negative, necessarily coercive aspects of worldly rule while urging his followers to obey on scriptural grounds. This was an important departure from contemporary Catholic thinking, which tended to ground civil power in the natural order of creation and to see that order in a much more positive light. Of course, grace and spiritual gifts were necessary to reach perfect, eternal bliss, but many Catholic authors thought that human societies could and should aspire to what they called “natural beatitude,” a state of flourishing which was important in its own right. The church could then guide people to the superior state of spiritual bliss that awaited the saints in heaven. The revival of Thomas Aquinas’s writing in the early sixteenth century, with its emphasis on the value of a natural order perfected by grace, strengthened this strand of political thinking while also elevating the church above merely natural rulers. In their efforts to re-evaluate magisterial authority, Luther and his followers were careful to avoid this Catholic position, with its sense of continuity between political and spiritual power.

Yet the strict division Luther had envisaged between the spiritual and the worldly was hard to maintain in the face of the Peasants’ Revolt of 1524-5. Hundreds of thousands of commoners in Germany and central Europe rose up against their feudal overlords, calling for an end to economic as well as spiritual oppression. Encouraged by Luther’s message of Christian liberty and his attack on papal tyranny, their leaders demanded an end to tithes and serfdom, and drew heavily on the New Testament to make their case. Luther was horrified that his message could have been interpreted in this way and supported the authorities in their brutal suppression of the movement. He insisted that the liberation of the gospel applied only to spiritual matters and that it did not disrupt earthly hierarchy. For him, a Christian could and should still act as a magistrate or a soldier, even where this entailed violence, but he did so not as a Christian but as an officeholder. In his private capacity as a Christian a person may not kill or injure, but when he took up a role as a public officer he needed to put this Christian identity to one side. As a magistrate he must execute justice and judgment, if necessary delivering capital sentences – moreover, he could do so in good conscience. Yet, as Luther’s tortuous efforts to explain such mental gymnastics show, even he realized the psychological difficulties involved.

In the aftermath of the Peasants’ Revolt, therefore, Luther’s sense of the scope and purpose of civil authority began to shift as he moved towards according a more positive role to magistrates. The turning point for him came in 1527 when he realized that the church in Saxony could only be reformed with the help of the Elector, and he found himself in the awkward position of having to justify magisterial interference in church affairs. On the one hand, he denied that the Elector, as a worldly magistrate, should have any say in the running of the church – instead he claimed that the Elector acted in his capacity as a private Christian, trying to do his best for the church. On the other hand, he realized that without the support of the civil power it would be impossible to enforce any changes, and so he argued that the Elector had the duty to maintain peace and unity by punishing those who refused to comply. Luther justified the Elector’s role under present, exigent circumstances, but not in such a way as to set a precedent for state control.

Luther’s own stance on church government was complex and nuanced. But while he himself was careful not to cede too much ground in church matters to earthly rulers, many of his supporters showed no such restraint. In the city of Nuremberg several councillors insisted that the magistrates had a duty “to use their office to the glory of God” and to cast out idolatry and superstition. They were beginning to suggest that a magistrate should strive to promote true godliness, rather than seek to subdue sin, as Luther had argued, or pursue merely natural beatitude as in Catholic theology. Meanwhile, Luther’s chief ally, Philipp Melanchthon, had also come to see worldly authorities as a means to promote the glory of God. As the 1530s wore on, Melanchthon grew impatient with lukewarm princes who seemed far too content to leave the task of reformation to the clergy. As a result, he began to demand more vehemently that the magistrate must ensure the practice of true religion. By 1539, when he wrote an influential tract on the duty of princes, he could even argue that “God wishes governments to exist for the sake of the church.” In Melanchthon’s view, it was now up to temporal authority to secure spiritual ends.

Melanchthon’s argument can seem at odds with Luther’s, but it flowed from similar principles. Both men believed that humans required the gospel and the law; the law restrained sin and made earthly life possible while the gospel held out the promise of redemption. There was no neutral space between the two, no “natural beatitude” to which a human society could aspire without grace. Both men rejected the Catholic division of labor whereby civil powers aimed at earthly ends and the clergy looked after spiritual ones. Furthermore, Melanchthon took up some of the hints in Luther’s writing about natural law, describing it as the God-given ethical standard for all human societies encapsulated in the Ten Commandments. The magistrate’s job was to enforce this law that, as the first set of commandments proved, concerned religious worship as well as earthly morality. Where Luther had shown that the magistrate was responsible for maintaining order on this sinful earth, Melanchthon now explained that God’s definition of order included proper religious worship.

Melanchthon’s argument quickly became mainstream within Protestant circles. Its main outlines were followed by John Calvin in his seminal Institutes of the Christian Religion, printed in ever-expanding editions between 1536 and 1560. Here Calvin explained that spiritual and secular government were distinct but compatible and that the duty of the civil magistrate was to “foster and protect the external worship of God, defend pure doctrine” as well as to ensure outward peace and good order. Ideally, magistrates and ministers were working towards the same end – the godly commonwealth – but their means were different. The former used coercive power (“the sword”) and the latter used the spiritual weapons of the word and the sacraments.


Perhaps the most pressing political question for the early Reformers was the legitimacy of resistance to the Holy Roman Emperor. We have seen that Luther initially condemned armed resistance as incompatible with the Word of God, but in the face of a growing Catholic threat to the fledgling Lutheran Church this position became hard to sustain. From 1530 Luther began to accept that resistance, even against the Emperor himself, might in some circumstances be permissible. At first Luther appealed to the imperial constitution, arguing that if it allowed princes to take up arms in their own defense then he, as a theologian, would not condemn this. Luther’s argument maintained the distinction between temporal and spiritual, but it was hardly likely to reassure anyone concerned about violating scriptural commands. Furthermore, it assumed once more that human beings could compartmentalize themselves, erecting a wall between their roles as lawyers, magistrates and princes, and their own Christian faith. Soon, Melanchthon and others crafted a more persuasive argument, rooted now in scripture and natural law. They argued that all magistrates, as Christians and as human beings, had a duty from God to protect and defend their subjects, even against the Emperor. The commands to obey might apply to private Christians, but men who were Christian magistrates had to love their neighbors by defending them.

Unfortunately for the Protestants, when military conflict with the Emperor came they found themselves generally on the losing side – but from this defeat more radical ideas began to emerge. In 1546, the Emperor Charles V crushed the Protestants at the Battle of Mühlberg, reversing their territorial gains of the previous two decades. Only a few cities resisted the imperial tide, of which the largest was Magdeburg. Under siege from 1550, Magdeburg sought desperately to rally fellow Protestants to their cause, pouring out pamphlets to justify their actions. The most famous of these was The Magdeburg Confession, in which the authors insisted on their right and duty to defend the true law of God, calling on their fellow Protestants to come to their aid. The Confession portrayed that law as both divine and natural, now emphasizing that it was binding upon all human beings and extended beyond any one particular territory. The principles underpinning the Confession would soon be taken up by embattled Protestants in France, Switzerland, and the Netherlands.

Protestant political thought was powerful, but also – despite Luther’s intentions – highly destabilizing. Initially the Protestants had tried to show that their demands were in line with existing constitutions as well as natural law, thereby maintaining the separation between worldly and spiritual authority. In Germany they pointed to the Imperial constitution, in France to the ancient public council that had once elected kings and prevented tyranny, in the Netherlands to the “Joyous Entry” agreed by all rulers when their reigns began. These mechanisms could, they hoped, be used to prevent Catholic rulers from implementing harsh religious laws. As the Catholic line hardened, however, the Protestants were forced to appeal beyond existing constitutions to more abstract concepts which transcended not only their own history but also their own territory, in a bid to stiffen the nerves of their co-religionists and to bring in outside support. Natural law proved to be a particularly valuable concept in this regard, because the Protestants saw it as a set of divine commands binding on all peoples, commands that no government could be allowed to contravene.

The Protestant resistance theory of the later sixteenth century was marked by these two commitments: to the unity of natural and divine law, at least in the sphere of ethics and politics, and to the universal force of its commands. These principles assumed ever greater importance as the levels of violence unleashed by the Reformation escalated further, especially after the massacre, on St Bartholomew’s Day 1572, of thousands of French Calvinists (Huguenots) by their Catholic neighbors. From the late 1570s, Protestants circulated their resistance theories more widely – anxious to win friends and allies from across Europe to their cause.

Perhaps the most notorious Protestant work of this period was the Vindiciae, Contra Tyrannos, written by an anonymous French author and published in 1579. Its author argued that “the laws of nature, of nations and civil law command us to take up arms against these tyrants,” and he called upon the French people to resist and reject their king and to restore justice and true religion. He then added an appeal to the princes of Europe, who ought also to assist in this noble endeavor. We must all help our fellow Christians, the author argued, whether they live in our own country or not, for the divine command of charity towards our brothers is itself the supreme expression of justice and natural law. Though the author was a Calvinist of some kind, like Luther and Melanchthon he denied that there could be any separate sphere of Christian ethics or duties. The natural law was our guide to our duties as Christians and as human beings; what the gospel brought was redemption and grace, not new moral standards.

The appeal to natural law in the Vindiciae, and similar texts, has suggested to some scholars that their authors wished to move beyond narrowly sectarian arguments and appeal across the confessional divide. Catholics themselves had, after all, long used the language of natural law to explain political authority and the renewed emphasis on Aquinas’s writing had strengthened this tendency. But Catholic natural law was in fact quite different from the Protestant version. For Catholics, the natural law directed humans towards natural ends and was complemented by a supernatural, divine law. The relationship between these laws structured the relationship between state and church, and Catholics – or at least those wishing to remain on good terms with Rome – tended to argue that the authority of the magistrate, based in natural law, was to some extent inferior to that of the church, based as the latter was on divine law. While natural law was authoritative in its own, earthly sphere, human beings looked beyond the natural and towards spiritual fulfillment, and for that reason they needed a Church that stood over and above the realm of nature. Broadly speaking, Catholics used natural law to protect the role of an independent Church, while Protestants used natural law to undermine it.

The Vindicae showed just how far the political thought of the Protestant movement had been transformed – but there is also important continuity. Most strikingly, Luther’s early commitment to non-resistance, based on the Word of God, had been reversed, and Protestants had come to see taking up arms as a binding duty. Yet these different consequences were drawn from similar principles, and particularly from Luther’s strong claim that God’s laws were universal commands from which no one was exempt. There were no special Christian moral laws; there was no space for a church or clergy who lived according to different norms (like poverty and chastity). In earthly, ethical, and political matters, there was only the natural law which was at the same time the divine law, given to human beings at creation and renewed through scriptural revelation.

Given the precarious legal standing of many Protestant communities, it is not surprising that their political arguments were designed to justify a wide range of actions to counter perceived tyranny or ungodly violence and persecution. Though their religious settlements were national and local, their political principles were necessarily internationalist, designed to attract support across state borders. They longed for rulers who would fulfill the role set out for them by Calvin and Melanchthon, upholding the true faith and casting down idolatry and superstition, and they wanted to assist each other in the fight to install such rulers. Although these arguments were necessary for survival, they were not based merely on expediency – they were rooted in Luther’s original rejection of the layered hierarchy of late medieval Catholicism. Luther’s efforts to blunt the social and political force of his own ideas by insisting on a separation between the spiritual and the temporal, a separation that ran through humans themselves, had foundered on the practical and psychological difficulties involved. Now, Protestants were able to generate radical and wide-ranging claims about the need to wage war against the forces of anti-Christ, claims based on both apocalyptic expectations and arguments from natural law.


By the 1620s, the destructive potential of militant religious loyalties was more apparent than ever. Not only had war broken out in Germany, a war that would last thirty years, but a temporary truce between the Spanish and the Dutch had also expired and parts of France remained in a state of civil war. The need for a Protestant account of civil authority that did not depend on the godliness of the magistrate was increasingly evident. It was at this moment that Protestant political thought took another decisive turn – one that would set its course for centuries to come. It can be traced to the work of Hugo Grotius, a Dutch Protestant in exile in France whose reworking of natural law would provide the starting point for the political thought of the Enlightenment. His On the Rights of War and Peace (1625) marked both the culmination and the closure of a period of political thought shaped by Reformation theology.

The power of Grotius’s writing lay in its demonstration of how Christian commitments, moral norms, and a strong conception of national sovereignty might all be combined and aligned, and the wars within Europe thereby moderated. To achieve this, however, Grotius needed to distance political authority, based on natural law, from Christian duties and Christian commitments. Only then could he find a way to explain how the rule of “heretics” and the ungodly might in fact be legitimate and binding, while also preventing the persecution of religious minorities. Grotius reactivated Luther’s separation between the temporal and the spiritual but he did so in quite a different way. Rather than present the two in a paradoxical relationship to each other, both ordained by God and yet entirely distinct, Grotius explained that they in fact stemmed from different principles. The authority of civil rulers in the temporal sphere was based on natural law, which Grotius saw as the principles given to us by God to preserve our own selves and our societies, while Christianity was based not on nature but on the historical revelation given to human beings through Jesus Christ. Furthermore, and in a stark reversal of Luther’s original theological insight, Grotius insisted that Christianity was in fact an ethical religion which could and should be freely chosen.

Grotius hoped to build upon Protestant and Catholic claims about the natural law basis of civil authority, but to insulate that authority from religious passions and principles. Unlike Melanchthon and the author of the Vindiciae, he did not believe that divine and natural law were identical; unlike the Catholics he did not see natural law as incomplete without the Church. In the aftermath of the Thirty Years War in Europe, it was Grotius’s account of natural law that was taught in universities across Europe. He offered to his Protestant readers a way of seeing magisterial and political power as valuable and legitimate in its own right, without needing to identify that authority with true Christianity or use it to promote the Church. It was this vision of politics that was taken up by John Locke and later authors, and is sometimes seen as the foundation for a liberal but Protestant tradition.

Grotius’s writing was – and is – controversial. Many Protestants found in his work a way of re-investing the magistrate with temporal, worldly authority, anchored in a natural law that no longer demanded full Christian obedience. Anglican readers quickly saw that this was compatible with quite strong claims for the authority of their church, as long as they traced that church to historical revelation and the original Apostles, and not to nature. Other Protestants felt that Grotius had betrayed them, secularizing natural law by distancing it from Christian ethics and revelation. They saw in him the beginnings of modern atheism, based on natural principles that seemed to have little to do with the Christian God. Both these reactions shed light on the problems faced by Protestants a century after the Reformation, especially those who sought to explain how a magistrate could be legitimate even if he did not share their faith. Even those who did not agree with Grotius found themselves discussing his ideas, particularly his claims about the natural law.

Several of Grotius’s themes were taken up by John Locke, especially in his 1690 Letter Concerning Toleration. This was an attempt to deal with perhaps the most obvious legacy of the Reformation in the religious sphere: the splintering of Christendom into numerous churches and denominations. The 1680s had seen a renewed effort at securing unity, by coercion if necessary. In France the Huguenots’ privileges under the Edict of Nantes were revoked and in England the Anglican establishment bore down heavily on religious dissent. Countering these trends, Locke asserted that persecution was both illegitimate and ineffective. Civil power existed for purely this-worldly ends like the protection of life and property, and the basis of its authority could be traced to the natural law. The magistrate was entitled to use force, but that was no way to effect a real and sincere change of heart. Churches, on the other hand, were voluntary associations in which people gathered to worship God as they saw fit. Locke denied that any church was superior to the state; instead he saw them as parallel institutions aiming at distinct and separate ends.

Locke’s political thought was very different from Luther’s, but its roots lie in the issues opened up by the Reformation movement. Since the 1520s, Protestants had tried to show how the magistrate’s authority could be divinely ordained while distancing it from the spiritual rule associated with Christ and the true Church. Luther’s strong claims about the Fall and the depravity of human nature led him to associate political power with the world of sin and violence; when his followers sought to rehabilitate politics they did so primarily on scriptural and religious grounds, even using a version of natural law closely tied to Protestant theology. Unlike the Catholics, they did not want to ground political power in an independent natural order. But they quickly found themselves caught on the horns of a dilemma. Luther’s initial position seemed to hand too much power to rulers, discouraging Christians at the time and in subsequent centuries from speaking out against misrule and oppression. In contrast, later Protestants came to seem too radical and subversive, unwilling to accept the legitimacy of any ruler who did not share their own religious commitments. Grotius and Locke sought a way out of this dilemma, but one which entailed the recovery of at least some elements of Catholic natural law.

It might seem today that the Reformation’s impact on political thought has run its course, and yet the questions Luther and his followers raised remain very much live issues. In a world of deeply held but divergent religious and ideological loyalties, state power needs to be legitimized in ways which are persuasive to people of faith and yet not dependent upon any particular confessional commitment. The heirs of both Luther and the author of the Vindiciae are still with us, keen to detach the state from true Christianity or to collapse politics into religion. Defending the value of politics and political engagement while still allowing room for thicker and richer commitments, whether religious or not, remains an important task in the current, increasingly polarized climate. If the solutions offered by Grotius and Locke are no longer viable, the challenge for our generation is to create a new and compelling vision of society, one able to inspire loyalty from religious and secular people alike.


Sarah Mortimer is Associate Professor of Modern History at Christ Church, University of Oxford. She is the author of Reason and Religion in the English Revolution (2010) and is currently working on a history of political thought from 1517 to 1625 for Oxford University Press.


Commenting has been turned off.

Current Issue

bottom of page