Big & Rich's fourth studio album, Hillbilly Jedi, marks the reunion of one of the most celebrated duos on country radio today. Big Kenny and John Rich will release their new set of tunes, the followup to 2007's Between Raising Hell and Amazing Grace, on Sept. 18.

In the five years in between Big & Rich albums, the two singer-songwriters have been busy with their own solo careers, charitable efforts and growing families. John released his debut solo album, Son of a Preacher Man in 2009, with Kenny releasing his The Quiet Times of a Rock and Roll Farm Boy album that same year. They've also thrown themselves into various philanthropic efforts, with Big Kenny traveling to Haiti and Africa, among several other places, to lend a hand to suffering communities. John, in addition to countless benefit concerts he's performed and organized, took up temporary residence in New York City to compete on "Celebrity Apprentice" -- winning the show and thus raising more than a million dollars for St. Jude Children's Research Hospital. Additionally, both halves of Big & Rich have welcomed new additions to their families since the duo's last album. John and wife Joan welcomed their first son in 2010 and second son in 2011. Big Kenny and wife Christiev adopted a baby in 2010, giving their older son Lincoln a little brother.

Hillbilly Jedi will include a song or two co-written with Bon Jovi's Jon Bon Jovi and Richie Sambora, who also helped inspire the album's title. The album's first single is the inspiring "That's Why I Pray," which was written by Sarah Buxton, Blair Daly and Danelle Leverett. Watch the "That's Why I Pray" video below, and pre-order Hillbilly Jedi here.

Watch Big & Rich's "That's Why I Pray" Video

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