Alan Jackson was a dozen studio albums into his successful country music career when he decided to do something he'd never done before: release a gospel album. Precious Memories -- what turned out to be the first of two projects by the same name -- arrived 15 years ago, on Feb. 28, 2006.

Jackson had previously released two Christmas albums in addition to his string of Top 5 country records, but Precious Memories was a particularly personal project; in fact, it was never intended to be heard widely. The country star originally recorded the tracks as a Christmas gift for his mother, Ruth, but an executive at his record label, Arista Nashville, heard the recordings and persuaded Jackson into releasing them to the public.

"[My wife] Denise kept telling me back then, ‘If you do these old hymns and do them like people remembered them in church, people are going to buy that thing.’ I said, ‘Okay,’ but we didn’t make the album with the intention of going out selling a bunch of albums. It was just an honest effort to do something sweet for our mothers, and I think that was a part of the feel of it," Jackson told Country Weekly in 2013. "It was just a sweet, honest, simple production and rendition of them."

Produced by Jackson's go-to producer, Keith Stegall, Precious Memories contains 15 traditional hymns, from "Softly and Tenderly" to "How Great Thou Art;" on "'Tis So Sweet to Trust in Jesus," Jackson's wife and their three daughters, Ali, Dani and Mattie, offer backing vocals. The songs are all ones the country icon remembers singing in church as a child.

"I'd stand up and sing when the congregation was singing out of the hymn book. Some of those melodies are a little tricky for a kid unless you knew the song real well, but I don't remember thinking much about it. Everybody just stood up -- if you didn't stand up, you know, everybody was staring at you -- so you had to stand up and act like you were singing anyway!" Jackson recalls. "But I went on to sing as a teenager. They had some organizations and choirs, and I remember singing in those some.

Arista Nashville

"And those were some of the early development for me as a singer, and that was probably the early days of getting a little confidence as a singer," he adds. "The church and the activities that went with it affected me as a singer."

Denise Jackson was right: People did buy that thing. Precious Memories debuted at the top of the Billboard country albums chart and at No. 4 on the all-genre Billboard 200. The RIAA certified the project platinum that August, and at the 2007 Gospel Music Association Dove Awards, the record was named Country Album of the Year.

"I had so many compliments from fans and even people who aren't really country fans. It just overwhelmed me," Jackson admits of the response to the album. "People have told me -- all over this country and even other parts of the world -- how much they loved that album. It's not just people older than me. I've seen young kids at my shows who have on the T-shirt that had the cover of that gospel album on it."

Seven years later, spurred by both fans' requests and his aging mother and mother-in-law, Jackson added to his collection of hymns with Precious Memories Volume II, released on March 26, 2013. That 11-song album includes "Amazing Grace" and, finally, the record's titular hymn, among others.

It, too, was a hot-selling project: No. 2 on the country albums chart, No. 1 on the Top Christian Albums chart and No. 5 on the all-genre Billboard 200. It also earned platinum status, in 2018.

In 2016, Jackson combined his original Precious Memories and Volume II into the Walmart-exclusive Precious Memories Collection, which included two brand-new songs: "That's the Way," which Jackson sang to his wife on their wedding day, and "It's All About Him," inspired by Denise Jackson's book of the same name.

Jackson stayed busy in 2006: That September, he released a new country album, Like Red on a Rose. Produced by Alison Krauss, it became his ninth record to hit No. 1 on the country charts.

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