The authors of the popular hymn "In Christ Alone", Keith and Kristyn Getty, are bringing their popular holiday concert tour, "Joy - An Irish Christmas", to cities around the U.S. for the fourth year in a row. This time, however, their traditional set of Irish folk music, bluegrass and hymns will include one unlikely Christmas carol that addresses the persecution currently facing Christians worldwide.

The decades-old carol, "Thou Who Wast Rich beyond All Splendor," has been freshly arranged for this year's concert and comes mid-way into the show's second half, according to a press release made available to the Gospel Herald.

"Our concert tour celebrates what is at the heart of the holiday: the story of the birth of Jesus. Yet, this year, somewhat surprisingly and perhaps ironically, we feel especially compelled to include this carol, given recent and ongoing tragic events taking place around the world where people are being killed because of their Christian faith," says Getty.

The beautiful hymn was written by Frank Houghton, an Englishman in China in 1934, and was inspired by the martyrdom of two Wheaton College graduates who were brutally beheaded in China where they were missionaries.

Lyrics include the powerful lines: "Thou who art love beyond all telling/ Saviour and King, we worship thee/ Emmanuel, within us dwelling/ Make us what thou wouldst have us be."

"Houghton, who was the Bishop of East Szechwan and the general director of China Inland Mission, traveled throughout the region trying to encourage missionaries during this desperate time where deep sorrow, questioning and fear had engulfed many of the people. While in the mountains of Szechwan, Houghton took a theme from 2 Corinthians 8:9 ('though He was rich, yet for your sake became poor...'') and transformed it into a stunning hymn, inspired by the Christmas narrative," says Getty.

Amazingly, in the decades that followed these killings, the Christian population in China has grown exponentially from an estimated 100,000 in 1932 to millions today.

"As it has been said, 'The blood of martyrs is the seed of the church'," says Getty. "Today, with Christian martyrdom on the rise, we felt the story so beautifully told in the lyrics of this hymn would again, as it has for decades, calm us, inspire us and encourage us."

Running from Dec 1. to Dec. 22, "Joy-An Irish Christmas" is coming to a number of cities around the U.S. and is described as a "lively celebration of the birth of Christ as told through an evening of traditional holiday carols, contemporary hymns, Irish folk music, bluegrass and spectacular step dancing."

This year, over 60,000 people are expected to attend the show, which also features the Getty's band of virtuoso musicians from North America and Ireland, a multi-generational choir and other special guests.

According to a press release for the show, the first half of "Joy-An Irish Christmas" is a "village celebration," featuring festive and up-tempo songs, including traditional carols, while the second half is more reflective, including the Getty's' contemporary carols and hymns that tell the Christmas Story.

Coinciding with the 2015 tour is a "Joy-An Irish Christmas" concert special airing on Public Television stations across the country. Click here for a complete list of stations near you.