In his 1929 book The Social Sources of Denominationalism, H. Richard Niebuhr explores how the nature of the church is informed by its relationship to the state. You probably know in the early days of Christianity, the church was persecuted by Roman authorities. By the early fourth century, things had changed: we have the emperor Constantine, who is remembered as the first Roman emperor to convert to Christianity. After that point, Christianity becomes increasingly a part of the Roman cultural infrastructure. It’s not that the church is straightforwardly an instrument of the state – rather, they mutually inform and change each other. “Christian leaders could regard the Caesar as a divine representative,” Niebuhr writes, “the political head of a new theocracy.” At the same time, the mission of the church underpins the imperial ambitions of Rome: “the continuance of a universal church was predicated on the continuance of a universal empire and the establishment or maintenance of a universal culture.” The state supports the church and the church supports the state. They become interlocking, mutually reinforcing systems.

That close relationship, Niebuhr argues, is one of the social sources of denominationalism. We have different denominations partly because the church had a close relationship to the state, and because the state doesn’t last in the same format. “The accommodation of Christianity to the prevalent culture, which the position of a privileged church made inevitable, was bound to involve the church in every disintegration of cultural unity.” In other words, as different cultural groups grew to prominence and built up their own identity independent of the central Roman empire, divisions in the church appeared in much the same way. Thus the Eastern Orthodox Church, drawn up along the cultural boundary between “Hellenic East and Roman West.” And, later down the line, nationalist cultures of the Renaissance give birth to the national churches – to Anglicans, Presbyterians, to Lutherans in the German churches. Perhaps we see the same principle at work today as well.

In some ways Niebuhr’s argument doesn’t quite line up with our experience of the church today. He was writing in 1929, just about a hundred years ago. It’s not all totally applicable. And yet he gives us some terms that can help to shape our understanding of the modern church. For example, when the church is closely aligned with the state, Niebuhr suggests that the church represents “the institutional and authoritarian as opposed to the individualistic and democratic conception of Christianity.” The national church adopts the relationship to its people that the state adopts towards its citizens. The doctrinal differences between denominations, Niebuhr argues, “do not obscure the underlying unity of the common conception of the church as an institution rather than as a voluntary society, of the sacraments as a means of grace rather than as symbols of confession, of the creeds as standards of doctrine rather than as confessions of faith.” You can see the different levels of agency in each example – where the sacraments are means of grace, and where the creeds are standards of doctrine, they are assets belonging to an institution that might be bestowed upon obedient, conforming subjects. In the other examples – the sacraments as symbols of confession, and the creeds as confessions of faith – these elements belong to the people, who almost just happen to deploy them communally.

We can use this language as a way to think about power and agency in the modern church. Which churches wield doctrine as a tool of social control, as a way of determining who’s allowed in and who’s not? Which churches reserve access to the sacraments as a means of grace? We might be tempted to say that these traits describe all churches – and maybe to some extent that’s true. But there’s a counterbalance in the fact that religious faith today operates under much more of a consumer model. For a lot of people – I think especially a lot of younger people – church is a lifestyle choice, in much the same way as yoga or veganism. The church only has as much authority as you give it. If you don’t like one, you can go and find another. There aren’t the social consequences of breaking away from a state church – as seen, for instance, in the Great Ejection in the 17th century, where two and a half thousand priests were disbarred from the Church of England (and also therefore barred from public office) for refusing to adhere to the new Book of Common Prayer. That’s not the sort of thing that happens any more. In most places, the church isn’t as close to the state.

And I think there’s something of an existential question for churches about how they function in the wake of this separation. In Niebuhr’s account, this close relationship between church and state has existed in some form, across various countries and continents, for the best part of seventeen hundred years. As the church loses that close connection to the state – especially with the dissolution of cultural taboos around divorce, homosexuality, and abortion – how do they cope with that change? How do they understand it and move forward? In practice we can observe a range of different responses. Some dig in their heels, serve as the conservative bulwark trying to stem the tide. Some limit their social control to the borders of their community. Out there, they say, people do all sorts of things – this is how we behave in here. There’s still a strong push for conformity, for obedience to institutional authority, but the limits of that power are strictly demarcated. And some change. Some accept the new social norm. Critics might describe it as accommodation, capitulating to the ways of the world. Niebuhr would say that’s nothing new. The church has been deferring to state power for a very long time. Conservatives just aren’t used to being on the outside of that equation.