Keith and Kristyn Getty released their holiday album, Joy — An Irish Christmas, last year. They also performed their first Christmas tour in 2011. The Nashville-based Irish couple is on the road again this holiday season for what’s become an annual Christmas tour.

“It’s really growing,” Keith Getty said of the tour that will reach 18 U.S. cities this year, including Baton Rouge. “And next year, because the growth of the whole thing has been overwhelming, we’re doing a concert-hall tour only. We’re very thankful and we’re very excited.”

As the tour’s title says, it’s an Irish-themed show featuring an Irish piper, Irish fiddler, Irish dancing and the guitarist who performed for the Broadway production of the blockbuster Irish musical, Riverdance.

Adding even more Irishness to the concerts, the Gettys either wrote or arranged everything selection. In addition to holiday music, the performance features high-energy traditional reels and jigs. After the concert, too, the musicians gather in theater lobbies for a post-concert jam, known in Ireland as a session.

Keith and Kristyn Getty met in 1999.

“We were just friends for several years,” Keith Getty recalled. “It took her a few years to realize that the extra weight I have is just lovable stuff that you can hug. We got married June 16, 2004. We’ve been together every day since.”

Kristyn Getty writes songs with her husband and sings lead vocals. Her husband affectionately calls her the most attractive person on the stage. As for their songwriting partnership, that’s a blessing, too.

“There’s an honesty, the inherent honesty you have with a wife that you don’t have with your professional partners,” Getty said. “That also can have extra bite, or be extra painful, but, ultimately, it’s extra honest.”

The Gettys left their wee, tiny house in Portstewart, County Londonderry, Northern Ireland, for a planned two-year sojourn in the U.S. The two years got extended to four years and, following some time off, the couple moved to Nashville.

“We loved it so much, we bought a home there,” Getty said.

Nashville being a musical hub for country and Christian music, it was a logical spot for the Gettys to land. They’re among the world’s top composers of Christian hymns.

The Gettys released their latest album, Hymns for the Christian Life, in October. It features guest appearances by bluegrass stars Alison Krauss and Ricky Skaggs and, from the Irish music group Clannad, Moya Brennan.

“I’m primarily a hymn writer,” Getty explained. “Most of the Christian organizations in the world are based in America. Increasingly, large churches, conferences, universities and leaders over here were asking us to come over and bring our music.”

Getty comes naturally to music and hymn writing. His mother taught piano; his dad was a church organist. Only church music and classical music were sung in their home. Nevertheless, Getty loved the traditional Celtic music of the British Isles.

“I love lilting melodies,” he said. “If somebody listens to our music, they’ll hear all those influences and that, really, was the thing that pushed me forward.”

Getty seeks to both rediscover and reinvent the hymn genre.

“I want to create timeless melodies that every generation can sing,” he said. “I’ve never cared to be the cool guy of the moment. I’ve always been interested in doing things that have lasting value. You avoid definition then. We can play in a cathedral, a little church, the Grand Ole Opry, the Royal Albert Hall. So many wonderful and contrasting experiences.”

When Getty writes hymns, he aspires to qualities he finds in hymns that have endured through the centuries.

Great hymns, he explained, “they usually are poetic and theological. They look at the vastness of God and the vastness of the universe, and the honesty and passion of human experience. They aren’t contrived, they aren’t manipulative.

“They were written with beautiful folk and classical influences that made the melodies classic. It’s high art, in a way, but it’s really the very best of popular art. And it’s music you carry generation to generation.

“The third thing is, hymns are great to sing in groups. I come from Irish culture, where all of our folk music is shared. Whether we’re in a pub or in a church or in a family home or at a sports game, we sing together. That’s the beauty of our art, that it’s to be shared.”