Florida Georgia Line got a little (well, actually a lot of) praise and worship going in Atlanta for their Saturday night (Aug. 31) show, when a very special guest joined on stage and got the entire audience singing along to a beloved Christian classic.

"We've never done this before, but real quick, God really does have a sense of humor," the duo's Tyler Hubbard noted on stage. "Because a few months back we got to meet one of our heroes. We ended up connecting with him, and building a friendship and a brotherhood."

That new "brother" just happened to be contemporary Christian legend Chris Tomlin, whom Hubbard further explained was an influence when he and Brian Kelley were growing up leading worship in church.

When Tomlin appeared on stage, the crowd roared. "This is one of the coolest moments for us," raved Hubbard. "Truly a full-circle God thing!"

Tomlin launched into his 2004 hit "How Great Is Our God," a song that Hubbard noted "we've sung hundreds of thousands of times in church." The audience, remarkably, all seemed to know the lyrics, providing a singalong chorus that was truly uplifting.

Indeed, Florida Georgia Line noted the magic of the moment, saying on social media that they were "in awe" of the collaboration, and urging fans to watch the entire clip: "Y'all gotta swipe a couple times but swear it's worth it."

The duo's Can't Say I Ain't Country Tour wraps on Sept. 28 in Irvine, Calif.

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