by Alexander Collin

Sarah Mortimer is Associate Professor of Early Modern History at Christ Church, Oxford. She is especially interested in the relationship between political thought and religious ideas. Her work focuses on a period when new ideas about salvation, about political life and about what it means to be human began to be expressed; after Martin Luther, Niccolò Machiavelli and Christopher Columbus the intellectual, political and religious landscape looked very different. Her research looks at how people sought to understand, explain, and shape their world in this fascinating and complex period.

Alexander Collin is a contributing editor of the JHI Blog. He interviewed Mortimer about her recent JHI article Warfare, Christianity, and the Law of Nature and her ongoing research into theology and political thought in early modern Europe.

Alexander Collin: Let’s start with something relatively straightforward. How did you come to write this piece in the JHI? Where does it fit in your body of work as a whole and how does it relate to other things you’re working on at the moment? 

Sarah Mortimer: The immediate impetus for this piece was a conference organized by Ian Campbell as part of his “War and the Supernatural” project; the project is explicitly cross-confessional and that spurred me to thinking about how questions of warfare and natural law were discussed on different sides of the Reformation fault lines. For a long time, though, in fact ever since my undergraduate days, I’ve wondered how and why Christians see natural law as obligatory, how they understand its relationship to divine law and to the teaching of Christ.

This theme has been important in my recent work, including my book on early modern political thought (Reformation, Resistance, and Reason of State), and I want to develop it further in the future. My next project is tentatively entitled “Virtue beyond Law: Transformations in Protestant ethics 1500–1700,” and that will be an opportunity to look in more detail at how early modern Protestants understand the duties of natural law and their relationship to Christian ethics. I’ve been very fortunate to find colleagues to discuss these questions with, including Ian and his team, and so it was great to be involved in the conference and then write up my paper for this cluster.

AC: Turning to the substance of the article: The distinction between what is licit and what is required is a major part of the debate over warfare that you discuss here. Is this a distinction which recurs in the philosophy and theology of this period? Are there other major arguments which turn on this structure? 

SM: I think this distinction is a helpful way for Thomist Catholics to make sense of the natural law, and to find a way to explain those acts which fall short of Christian perfection but which are not in themselves wrong. The basic structure of their argument is shaped in many ways by their theology of salvation, and by the Catholic idea that there are some acts which are supererogatory and meritorious, in other words acts that we do not have to do, that we are not obliged to, but which gain us merit if we do carry them out.

These are sometimes called Counsels of Perfection, and one good example that is often used is visiting the sick in time of plague. It’s not wrong to stay away from ill and contagious people, but going to visit them is an act of charity that goes beyond strict duty and which counts as a good work.

Of course, Luther will contest all of this—but that then raises important questions for Protestants about ethics, politics, and so on. I look at some of the consequences for political power in my recent book, and in an article on “Counsels of Perfection” but the ethical implications for both Protestants and Catholics remains to be fully explored.

AC: I got the sense that, in each of the philosophical positions on natural law, warfare, and Christianity that you discuss in this article, there is a mixture of a kind of academic, abstract discussion on the one hand, with a response to emerging political events on the other. For example, Cajetan is engaging with the church fathers, but he is also thinking about the principalities of the Holy Roman Empire; or Luther is considering this issue within his overall vision of Reform, but he is also responding to relations with the Ottomans.

To what extent should we read these writers as principally concerned with concrete political advice, versus to what extent is this more a moral and theological debate, in which practical applications are of secondary importance? Or would you reject that dichotomy altogether? 

SM: I’m glad to hear that you felt the debates were both academic and practical; for me, the most exciting aspect of the history of ideas is the way that it can help us understand how and why particular arguments were developed and deployed at particular times. And for me the story always includes the intellectual resources that were available, the agendas of the people involved, and the practical circumstances in which the debates were lived out.

One of the aims of my own work is to show how authors and thinkers were also people of flesh and blood, who lived in particular contexts that helped to shape their arguments. Cajetan is a good example of this. He is writing in the context of disputes in the Church, over the role of Council and Pope and over theologies of salvation, but he is also aware of the situation of Italian cities and the Papal States during this unsettled period of warfare in the Italian peninsular.

Meanwhile, if we turn to the Reformer Peter Martyr Vermigli, he is keen to win over godly magistrates (like Edward VI of England) and to encourage them to commit to enacting the Kingdom of Christ as far as possible. For him, it is really important to show that war and coercion are legitimate, indeed often necessary, for Christian magistrates and that this is the true message of Scripture. Biblical commentaries become an extremely effective way of making this case—and particularly commentaries on passages that talk about kings and magistrates, and the warfare in which they engage.

AC: You identify part of what makes the Protestant view distinctive as their “agenda of unifying natural law and Christian ethics.” Why don’t Catholics also regard that unity as necessary? Or if they do, why are they less troubled by it than the Protestants? Is Baius moving in this direction with his insistence that grace and natural law are inseparable? 

SM: Thanks for highlighting this—I think that the Catholic view of natural law and Christian ethics is really subtle and complicated, and modern scholarship is just catching up with this. Part of the answer goes back to what I was saying about the Catholic position on merit and supererogation, but it is also connected to developing ecclesiologies and views of the Church. Catholic views on merit allowed theologians to claim that the Church controlled a “treasury of merit” which it could dispense to believers, hence the creation of indulgences which facilitated the transfer of this merit.

Also, the Catholic view of the authority of clergy and the value of monasticism encouraged a sense of hierarchy between lay and spiritual offices—and of the action appropriate to each. Rulers who were entangled in earthly affairs would, on this reading, be inferior to clergy who focused on spiritual activities and acts of charity.

Then, in the early sixteenth century, the Conciliarist claim that Church was like a commonwealth prompted men like Cajetan to insist instead that it was grounded in divine rather than natural law. Protestants—especially Luther—saw all these claims as connected, on the grounds that all of them elevated the Church and the clergy, but I think for the Catholics there is a process of debate through the sixteenth century about just what, if any, the connection might be between them.

Going back to your question: the Catholic position is of course designed to elevate the status of Christianity above nature and above merely civil and natural duties, while still taking the earthly and political world seriously. So I think it’s not so much that the Catholics are untroubled by the question of unity, but rather that they are trying to find a way to distinguish between the two that enables them to achieve their aims and defend their Church.

One important catalyst for debate about this is the question of excommunication, because not only do Catholics believe that the Pope can excommunicate rulers, many of them also believe that excommunication makes the ruler illegitimate in a Christian commonwealth and so the people are absolved of their duty towards an excommunicate (ex)ruler. At the end of the sixteenth century the great Catholic theologians Robert Bellarmine and Francisco Suarez defend the power of the pope to depose rulers on the grounds that spiritual power is higher than civil authority, because the latter is based only in natural law (and human beings are called to higher, spiritual purposes and duties).

This view, though, is very much a Thomist Catholic view, and as our cluster shows the Thomists weren’t the only Catholics to reflect on these questions. As you note, Michael Baius took a different approach, and was quite hostile to the claim that we can think about natural law as somehow abstracted from grace. For him, the problem seems to have been that it encouraged people just to follow natural law—and natural law separate from grace didn’t seem very moral. Indeed, it offered an excuse for people to make compromises, for example with the Protestants in the Netherlands, and thus it devalued true Christianity.

I’ve become quite interested in these debates as a historian, but it might be worth pointing out that they are still live issues among Catholic theologians. Debate kicked off in earnest with the publication of Henri de Lubac’s Surnaturel in 1946—he was a French theologian who felt that the distinction between nature and grace that many Catholics had inherited from the early modern period was problematic because it cut the Church and the state off from each other. In response, he wanted to show how men like Cajetan and Baius had in fact misunderstood the true meanings of Aquinas and Augustine. His concerns were very much those of a Catholic theologian, but historians can still learn from his writing.

AC: For the last question on individual authors, I’d like to turn to Grotius. You trace the development of his thinking on warfare, Christianity, and natural law. What is the best way for us to understand those changes? Do they come out of dialogue with other scholars? Do they come out of his personal experiences of the Netherlands wars in his lifetime? Some other source? 

SM: Grotius’s life was a very eventful one, but it seems to me that one of the key moments in it was his imprisonment in 1618 when Maurice of Nassau and the Calvinists took power in Holland. Prior to that, Grotius was willing to defend the power of the state over the Church, but after that he was much more keen to keep Christianity and civil authority separate. (He still thought that basic religious belief could be enforced, but not distinctively Christian principles.)

But Grotius also seems to have become increasingly interested in the ethical dimension to Christianity. Like many people around him, he thought that Christianity should make a difference to one’s actions and morals, and he also thought that it would be wrong to coerce people into acts of Christian charity. I think that he is probably picking up this way of seeing religion from other Dutch Christians, particularly the Remonstrants or Arminians, and certainly he is in touch with them.

These contacts also lead him to study the Bible more intensively, to write Annotations upon it—and he begins while he is in prison by studying and annotating the Gospels, the parts of the scripture where Jesus’s teaching is most clearly expressed. And Grotius starts to suggest that Jesus’s teaching offers a higher ethical standard than any natural law or philosophy. Then he wrestles with what this means for the legitimacy of warfare—as a good Dutch patriot he is positive about the Dutch Revolt, but sometimes unsure how to square this with Jesus’s ethics.

AC: Your early work dealt a lot with Socinian thought, but they don’t make an appearance in this article. Is there are distinctive Socinian perspective on these questions?

SM: Yes! The Socinians were famous in this period for their clear assertion of the difference between natural law and Christian ethics. They were pacifists, at least initially, on the grounds that Christ forbade warfare, but they also engaged quite extensively with some of the natural law arguments for the legitimacy of warfare, and that made them unusual. The Socinians wanted to show that while natural law arguments may be valid in their own terms, they will not get you to heaven; only if you follow Christ’s teaching will you be rewarded with eternal life.

Though their sometimes rather blunt claims didn’t win that many people over to them completely, they did stimulate a discussion about these issues which caught the attention of people across Europe. For example, we know that Grotius was reading at least some of their work, and vice versa. As a graduate student I came across these debates and realized that often what made Socinianism so interesting to its readers was this view of natural law and Christianity, and that I needed to study it in much more detail!

AC: Lastly, with any article, some amount of material gets left on the cutting room floor, is there anything you wanted to include here but couldn’t? A writer or book you didn’t discuss? A point of clarification or qualification that didn’t fit?

SM: In many ways this article is a kind of bridge between some of the work I’ve already done on natural law, politics, and Christianity, and the work I want to do next on virtue and law. It was also a chance to say a little more about authors like Cajetan and Baius who feature only very briefly in my recent book (though there is so much more to say about both. . .).

The article—and indeed the cluster—is also a reminder of how many important early modern writers are out there, on whom there has been so little work. I sometimes think it is a shame that scholars cluster around a small number of canonical thinkers, and I hope that by broadening the scope of our enquiry we will have a better sense of the ideas of this crucial period.

AC: What you are working on now/next, are there any forthcoming publications readers should look out for?

SM: My next project is about “Virtue beyond Law” in Protestant Europe. In it I explore changing ideas about the relationship between virtue and liberty in the early modern period, and what they might mean for political and religious authority. While we might assume that virtue requires the possibility of choice, of acting otherwise, early Protestants denied this, insisting that humans need not only God’s grace but also strong structures of law and punishment.

And yet, by the seventeenth century, a very different case was being made. Influential Protestant voices were now emphasizing individual liberty and virtue, insisting that human beings must choose to follow the superior and demanding ethics of Christ while denying that these ethics could or should be binding upon all.  I want to look at how and why these new ideas about community, Christianity, and ideas of virtue arose, and say something too about their significance for our ideas of liberty and morality. It’s still at an early stage, but I have enjoyed trying out some of the ideas in seminars.

More concretely, readers might look out for a new volume called Time, History, and Political Thought edited by John Robertson and due out from Cambridge UP later in 2023. I have an article in it on “Christian Time and the Commonwealth in Early Modern Political Thought,” which looks at the relationship between natural law arguments and Christianity as a story that takes place in time.

There is more in it about Grotius, and particularly the ways he uses Catholic natural law thinking but places it within a rather different theological and temporal framework, connected to his own distinctive sense of Christian history. As this might suggest, the more I think about natural law in the early modern period, the more I realize how complex and fascinating it is! 

Alexander Collin is a PhD candidate at the University of Amsterdam where he works on northern Europe from the 1490s to the 1700s. His doctoral thesis aims to test the historical applicability of theories of decision making from economics and organizational studies, considering to what extent we should historicize the idea of “The Decision” and to what extent it is a human universal.

Featured image: Luther in front of Cardinal Cajetan during the controversy of his 95 Theses, 1870 (oil on canvas) by Ferdinand Wilhelm Pauwels, Public domain, via Wikimedia Commons.