“Secular.” It’s a word my teenage, Christian brain assumed had to be more or less synonymous with “sexual.”

Many people know better than that, but even highly-educated Christians still assume that “the secular” is intertwined with secularism. The category of the secular, they think, is a pillar of an anti-Christian worldview, or, at best, a purportedly neutral pluralism or liberalism that, in fact, crowds out religious faith.

But the secular is a category of the Christian worldview. It denotes the dimensions of life that are not specifically religious, but common to human beings in the present age. The distinction between “secular” and “religious” marks a divide, not between Christian and non-Christian people, but within every person.

In fact, I warrant that, prior to the rise of secularism, the word “secular” would not even have had negative connotations to Christian ears.

Let me explain.

Life in the Saeculum — This Age

The etymology of the word “secular” begins with the Latin word “saeculum,” meaning “generation,” “age,” or literally, “century.” From the adjectival form saecularis came the Old French seculer and, thence, the English “secular.”

According to the Oxford English Dictionary, the first use of “secular” is:

1. denoting attitudes, activities, or other things that have no religious or spiritual basis. [E.g.,] “secular buildings.”

Its synonyms include everything from “nonreligious,” “lay,” and “temporal,” to “worldly,” “earthly,” and “profane.” (Profane used to be much more innocuous as well.)

The second entry in the OED brings us to our first historical point of contact:

2. [Christian Church]

(of clergy) not subject to or bound by religious rule; not belonging to or living in a monastic or other order.

As reflected in this definition, Medieval Christendom distinguished between secular and religious clergy. The religious life was lived in monastic community or otherwise subject to a particular religious order. Those in the religious life vowed to follow Christ’s “counsels of perfection”: Celibacy, poverty, and obedience. These were the religious clergy.

Secular clergy, on the other hand, ministered in parishes amongst ordinary people. If, to our ears, “secular clergy” sounds like a contradiction, this simply demonstrates our distance from Medieval Christian understanding. For Medieval Christians, “secular” simply meant participation in common life.

Nevertheless, the Medieval distinction between religious and secular life and vocations reveals that Catholic Christianity did suffer from the temptation to escape the secular, to rise above it. The religious life was held to be higher than secular life. While society needed people to perform secular tasks, like government, warfare, and trading, those in the religious life purified themselves of these worldly enterprises. (I wrote about this tension in Catholic Christianity in Christian Realism: A Philosophy of Christian Action.) The Catholic Church even claimed to be above the jurisdiction of secular authorities.

Until a certain German friar took them down a few notches.

The Protestant Embrace of the Secular

Martin Luther, in his “Letter to the German Nobility,” criticized the Catholic Church for purporting to be above the realm of the secular.

Luther denied the Church’s claim to be free of the jurisdiction of secular, political authorities. He lambasted the artificial wall the Church had raised between “the spiritual estate” and “the temporal estate,” between religious and secular callings. He argued that all Christians were of the spiritual estate, even as they inhabited a variety of temporal professions:

“All Christians are truly of the ‘spiritual estate,’ and there is among them no difference at all but that of office.”

— Martin Luther, “An Open Letter to the Christian Nobility of the German Nation”

Luther’s word for these ordinary professions and callings was weltlich, literally, “worldly.” In English translation, it is primarily translated “temporal.”

The word translated “secular” also appears once in the letter: zeitlichen. (Zeit is time.) In that use, Luther jokes that, if the popes, bishops, priests, and monks are above secular life, then “the tailors, cobblers, masons, carpenters…and all the secular tradesmen, should also be prevented from providing [them] with shoes, clothing, house, meat and drink, and from paying them tribute” (p. 70).

In this polemic, Luther accomplished two things at once. First, he acknowledged the ordinariness and secularity of life: Even the pope needs someone to make his shoes.

Second: At the same time, he was dignifying secular life, even sanctifying it. Every Christian, simply in virtue of baptism, was of the spiritual estate, whether butcher, baker, or candlestick maker.

Now Luther did not take a secularist position. He did not say, “This whole ‘spiritual estate’ thing is balderdash. You’re all secular.” He said that all Christians are of the spiritual estate, in the variety of their secular and religious callings. The spiritual and the secular interpenetrate.

This is the actual content of Calvin and Luther’s doctrine of the two kingdoms. The spiritual and secular cut across all human lives. Even pastors need shoes and functioning plumbing. And even cobblers and barbers are priests who may approach God’s throne of grace, without the mediation of the Church. (I learned this lesson from the Davenant Institute and the writers at The Calvinist International.)

If I say, then, that “the secular is spiritual,” it must be recognized that is no less secular for all that. (I did write, and mean, those words in “Giving Up on the ‘Jesus Juke.’”)

Protestantism does not say, after all, that each Christian is part of a special religious order, holy and separated from secular things. No; Protestantism says that all Christians are of the spiritual estate, whether employed as preachers, politicos, or plumbers. And that preachers are as enmeshed in the secular world as politicos and plumbers.

Every Christian life is both spiritual and secular.

The Vibe Shift in a Secular Age

The history of how “secular” came to have negative connotations to Christian ears is one I’d like to know better. But I surmise that the rise of secularist and naturalist worldviews has a lot to do with it.

In response to the French Enlightenment and mid to late 19th-century thought – Darwin, Marx, Freud, and Nietzsche – contemporary Christians were put on the defensive. They took solace in separating from secular life, spiritualizing their vision of Christian calling, and viewing the world as a source of temptation and godlessness.

In so doing, we left behind the classical Christian worldview in which the secular, the temporal, and even the worldly had their place.

In our time, it is easy for Christians still to remain on the defensive. After all, secularism has proceeded apace. The world has, in certain respects, gotten more hostile toward Christianity.

But even when the world, i.e., the contemporary culture, is hostile toward Christianity, the right posture is not a defensive one. Aaron M. Renn, coiner of “the negative world,” said recently that it is time for Christians to seek friendship with those of the world. Our religious majority is gone. A posture of asser