Whitney Houston's gospel album is a testament to her faith: 'She served her purpose here in life'

At virtually every one of her concerts, Whitney Houston always included at least one gospel song on the set list.

It was a tribute not only to her upbringing, singing with her mom, Cissy, at New Hope Baptist Church in Newark, New Jersey. But it was also a testament to her strong faith in God.

"Gospel was the center of her gravity," says Pat Houston, Whitney's sister-in-law. "She always said, 'Wherever I go, it doesn't matter: I will always tell the world of the love that I have from Jesus.' And she was able to bring God's word to a broader audience through her music."

Shortly before her death in 2012, Whitney talked to Pat about doing a gospel project. Now, the late singer's estate is following through on her wishes with "I Go to the Rock: The Gospel Music of Whitney Houston" (out now), a 15-track album and accompanying DVD that celebrates her roots in the genre.

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The album features songs from "The Preacher's Wife" and "The Bodyguard" soundtracks, as well as six never-before-released recordings. The documentary special, meanwhile, is hosted by Whitney's friend and collaborator Cece Winans, and showcases 10 of her most memorable gospel performances on TV, including the 1988 American Music Awards and a 1990 episode of "The Arsenio Hall Show."

"Whitney's an incredible singer, but she just seemed to come alive with that music," says Barry Jennings, who produced the project. "I was impressed that she did gospel music on all these programs like 'Saturday Night Live,' so obviously, gospel was very near and dear to her."

Mervyn Warren, who produced and arranged most of the "Preacher's Wife" soundtrack in 1996, recalls witnessing Whitney's excitement for the genre firsthand. She helped curate much of the album, which includes songs "Joy to the World" and "I Love the Lord" with the Georgia Mass Choir.

In the studio, "I could tell how much fun she was having," Warren says. "She would interpret these songs in her own way, and from take to take, they would be different. We laughed and had a great time, but she really had a way of interpreting songs that remains unmatched."

"I Go to the Rock" also features previously unreleased songs "He Can Use Me" and "Testimony," which Whitney recorded when she was 17. Even at her young age, she had the staggering voice and confidence that went on to define her eventual pop hits.

With those songs, "she proved that (God) definitely used her while she was here," says brother Gary Houston. "There was a conviction when she sang songs that had to do with her beliefs."

Pat Houston says Whitney's faith was very important to her until the day she died. "I remember her mother giving her a Bible back in 1987," she recalls. "After all those years, she was still holding on to it. And in that Bible was an (inscription) her mother wrote that said, 'Never forget who you belong to.'"

Ultimately, she hopes this gospel project will help give "closure" to Whitney's fans.

"No matter the trials and tribulations that she had in life, she knew she could pray and how powerful prayer was," Pat Houston says. "We all fall short in life, but she knew where her strength came from. In her song 'Don't Cry for Me,' which she recorded many, many years ago, she said, 'Don't cry for me when I'm gone. My death was meant to be.' So even in her passing, (fans) should know that she served her purpose here in life. We can only hope that we can be as purposeful as she was."

"Music brings people together and brings out something good," Gary Houston adds. "It's great to know that she had an indelible mark on the world."

This article originally appeared on USA TODAY: Whitney Houston's family hopes posthumous gospel album brings closure