From atop a mountain in Galilee, according to Matthew 28, Jesus delivered his Great Commission, unequivocal in its instruction: “Go and make disciples of all nations.” For 2,000 years, across cultures and continents, Christians have heeded this evangelical Prime Directive, spreading the Good News through street sermons, paper pamphlets, highway billboards, television programs.

To this list, we can add online targeted advertising. Churches of all denominations are using Facebook and Instagram ads to reach pinpointed audiences in their communities, transforming the Great Commission’s “nations” into living, breathing (scrolling) individuals. Now, it’s, “Go and make disciples of all 18- to 34-year-olds within a 10-mile radius who prefer Chick-fil-A to Popeyes.”

In a recent TED interview, Roger McNamee, an early Facebook investor turned Big Tech critic, echoed what is now a cliché: “Facebook is the greatest advertising platform ever invented.” Last year, a then–84-year-old Sen. Orrin Hatch seemed confused on this point, asking Mark Zuckerberg how Facebook could “sustain a business model in which users don’t pay.” Zuckerberg’s response was fantastically terse—“Senator, we run ads.” Twitter erupted with jeers at Hatch’s expense, the joke being that anyone paying attention knows Facebook is fundamentally an advertising platform. Digital advertising has ballooned into a $100 billion industry, leveraged by Fortune 500 companies, political campaigns, and, increasingly, religious organizations. And while many smaller, rural, and liturgical churches are—like the senator from Utah—struggling to modernize, there’s a growing sense in the Christian community that digital outreach holds the key to its future.

The people prodding Christianity into the world of data-driven advertising are an earnest group: digitally savvy, passionate about social issues, inclusive (ecumenical in church-speak). They’re young, for the most part. (In church circles, “Millennials” and “Gen Z” are the headline subjects of conferences and summits. Churches are losing young people at a precipitous rate. It’s something of a crisis.)

Many large churches—defined as those with average Sunday service attendance exceeding 1,000 worshipers—employ “outreach ministers” or “communication directors,” folks whose jobs historically involved stuffing envelopes with paper mailers but now require traversing digital waters. Larger megachurches, with tens of thousands of weekly attendees, build social media teams that look an awful lot like those of big companies. And at smaller or medium-size churches (with fewer than 300 weekly attendees), it’s often a budget-minded pastor or member-volunteer managing online accounts. A pastor from Ohio told me about a Facebook campaign she ran advertising an Easter egg hunt. She spent $20, targeting parents with children. More than 400 people showed up. She attributed that turnout largely to Facebook.

Across the spectrum of church types and sizes, there’s an ongoing and spirited dialogue about how best to market Christianity in a secular age. The Church Communications Facebook group boasts more than 20,000 members: They discuss branding strategies, workshop ad copy, and share success stories (and the occasional Distracted Boyfriend meme). Many are concerned with reaching the “unchurched,” the going jargon for people not belonging to or connected with a church. This somewhat amorphous category includes “nones,” who claim no religious affiliation, as well as “marginally” or “previously” churched individuals, whose lapsed curiosity might be piqued by a well-placed ad.

Katie Allred—co-founder of the group and assistant professor of software development and digital media at the University of Mobile, a Baptist-affiliated school—cites the Parable of the Lost Sheep, in which a shepherd leaves his flock of 99 sheep to recover the wandering one, as biblical inspiration. According to Allred, “If your church has a marketing budget, you don’t want to use that budget to reach the 99. You want to use your ad budget to reach the one, so that someone who is far from Christ might be interested in learning more.”

Reaching “the one” means speaking the language of the culture, which has long been a pressing matter for Christians, from translating the Bible into German to performing Mass in the vernacular. Brady Shearer of ProChurchTools advocates a Facebook ad strategy based upon “intersectional moments” in which faith and society might coalesce. Rather than sharing Bible verses or, worse yet, fire-and-brimstone exhortations, churches should emphasize human stories and create calls to action around practical events: fall festivals, pictures with Santa, neighborhood block parties. You’re more likely to entice a local mom or dad with an image of an inflatable bounce house than an inspirational psalm. Shearer’s website suggests, “Don’t use Christian lingo in your copy, especially if you’re targeting your wider community. Create a laid-back, friendly feel to your ad.” In other words, to pitch religion, don’t come across as too religious. Speak casually, get people through the doors, and let your community do the rest.

An ad’s creativity is typically dictated by whom the church chooses to target. Facebook and Instagram offer a prodigious suite of targeting options, allowing users to filter ad recipients based on location, demographics, behavior, interests, and connections. In this respect, churches have a difficult decision to make: Do they target broadly and reach a wide audience or home in on individuals likely to be receptive to their message?

As Big Church bolsters its relationship to Big Tech, it will further dominate the “market share” of Christian Americans.

With the latter approach, churches often aim for individuals who have “liked” content related to Christianity or spirituality. Or they target first-time homeowners or new movers to a city. Or they leverage their congregations, an invaluable resource when it comes to digital outreach. From the pulpit, pastors can encourage Sunday worshipers to share content and “like” particular church events, thus receiving a boost from a Facebook algorithm that showcases trending events with a high frequency of likes. In addition, churches use membership lists to reach “look-alike audiences”—new people similar to those already attending a particular church. Not exactly a lost sheep strategy, but it’s effective.

As the “youth problem” compounds, young parents are especially coveted by churches, identified by their age, relationship status, life events, and/or purchase history. I heard from one church communicator who targeted minivan owners (i.e., families) with ads, and another who used geofencing to target a particular location at a particular time: an elementary school between the hours of 3–4 p.m., when moms and dads wait in a long line of cars to pick up their kids, killing time on social media.

Church communicators—more so than your average business owner or campaign manager— must engage in a complicated moral calculus when placing ads, weighing centuries-old injunctions alongside the shifting norms and capabilities of a tech-obsessed culture. Some told me that Facebook ads do feel “a little creepy,” and they aren’t even totally sure how Facebook does what it does. One former pastor said, “ ‘Marketing’ feels like a dirty word to many in the church, but who’s to say the Holy Spirit can’t reach a person through a Tweet or an ad or a Live stream?”

If formulating a marketing strategy feels overwhelming, churches might consult with a Christian-specific advertising agency (of which there are many)—or if hiring out is cost-prohibitive, they might attempt to copy Elevation Church, the gold standard in church marketing. Based in Matthews, North Carolina, Elevation averages nearly 26,000 attendees across more than a dozen locations. But it’s the church’s online presence that sets it apart. In 2018, according to its annual report, Elevation received more than 80 million sermon views across all online platforms.

The church’s chiseled, charismatic preacher—the Rev. Steven Furtick—is the centerpiece of its branding. Filtered Instagram stills and 30-second videos showcase his inspirational, if at times clunky, one-liners (“Joy is not a feeling; it’s a focus”). Furtick and his church reside firmly in the school of self-help, be-a-better-version-of-yourself marketing. (In part, this is what “Elevation” means.) The ads and posts are often framed from the perspective of a congregant in the crowd, providing a window to the “worship experience” (not “church service”) and Pastor Steven’s invigorating sermons. Or they might just share a simple reminder, maybe with retro-fonted text splashed over a two-fingered peace sign: “It’s the weekend. Did you hear us? It’s. The. Weekend. Which means time to rest, recharge, and get ready for church.”

Fewer people are. In the United States, more churches are closing their doors than ever before: Between 5,000 and 10,000 churches shut down each year. (The National Trust for Canada estimates that one-third of Canada’s churches will close over the next 10 years.) Alternative churches are sprouting in response: dinner churches, cowboy churches, virtual reality churches. Whether they’ll be fads or fixtures, it’s hard to say. In the meantime, the megachurches are thriving. As Big Church bolsters its relationship to Big Tech, it will further dominate the “market share” of Christian Americans, as young believers gravitate toward smooth-running operations. In this environment, smaller local churches will continue to wither. And while slick Instagram posts alone won’t reverse their fortunes, these ads-for-God suggest an interesting question: Who would Jesus target?

Future Tense is a partnership of Slate, New America, and Arizona State University that examines emerging technologies, public policy, and society.