Mr. Wagner acknowledged that Hillsong risked being criticized for participating, but said the documentary “fits right into the church’s M.O.,” which includes the evangelist knack for “being right at the forefront of using every kind of media possible to bring God to the secular popular consciousness.”

Michael John Warren, the director of MTV documentaries about Drake and Nicki Minaj, perked up a few years ago when he heard about a big music film that was kicking around Hollywood.

“‘They’ve sold tens of millions of albums,’” he recently recalled a friend saying at the time, “‘and they play sold-out arenas multiple nights in a row.’” Mr. Warren, best known for his Jay Z concert film “Fade to Black,” immediately imagined Coldplay or U2. “Awesome,” he thought.

But in fact, like many nonreligious Americans, he had never even heard of the group in question: Hillsong United, the primary musical engine for Hillsong, the stylish, internationally expanding Australian Pentecostal megachurch that counts Justin Bieber and Kevin Durant among its flock.

“Why would I ever make a Christian rock film?” the director, who was raised Catholic but is now closer to agnostic, said. “You could have told me it was about ISIS or Satanism and I would’ve said, ‘Sounds edgy and cool — let’s go!’ But you say ‘Jesus’ and I’m like, ‘Whoa, whoa, whoa, no thank you.’”

Yet it took only one Hillsong service for Mr. Warren. 43, to overcome his knee-jerk prejudice, if not quite convert. Moved by the youth, diversity and emotion of the congregation — plus the disarming pop songwriting — the director signed on for what would become “Hillsong — Let Hope Rise,” a slick, stirring concert film out Friday that details the sound and mission of the most impactful group in evangelicalism.

Hillsong United serves as the public-facing flagship of a three-pronged music empire, which also includes a more church-centric division (Hillsong Worship) and a youth-focused arm that develops talent (Young & Free). Together they have sold some 20 million albums, dominating contemporary Christian music; the recent smash “Oceans (Where Feet May Fail),” a tear-jerking nine-minute ballad à la Coldplay’s “Fix You,” has spent more than two years in the top five of Billboard’s Hot Christian Songs chart after more than a year at No. 1.

With Mr. Warren’s secular lens lending outsider credibility, “Let Hope Rise” attempts a delicate balance — glorifying the band onstage and off to please its faithful (potentially millions of ticket-buyers) while not coming off so uncritical as to alienate curious nonbelievers.