Actor Stephen Baldwin said Justin and Hailey know marriage is a holy commitment and want the wedding to reflect that.
He told US entertainment news site TMZ: "I just think that as Christians and as believers they understand that if you don't have God's spirit working in your marriage it just makes it more and more difficult to make it work and have peace and find happiness," he told TMZ.
"Weddings and marriage are supposed to be a holy commitment, one onto another."
His statement comes after the couple's save the date was revealed.
Baldwin said it will be a "very fun wedding" in South Carolina with a lot of "their pastor friends and Christian friends around them".
"My only job is just walking my princess down the aisle," he added.
Justin and Hailey married last September in a civil ceremony.
In an interview with Vogue Magazine Justin revealed that the two waited until they were married to have sex.
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