DONNA SUMMER ends her newest album with a resounding "I Believe in Jesus."

Black gospel superstar Shirley Caesar includes Bob Dylan's "You Gotta Serve Somebody" on her latest LP.

The Commodores charge up the charts on the strength of their gospel tune, "Jesus Is Love."

The phenomenon is Christian music, and of the 7,000 radio stations in America, 1,400 are playing it. It's one of the fastest growing formats on radio today, as strongly defined as disco, country or Top-40. The songs are recorded both by well-known secular acts, and by some 500 performers who are the nucleus of a growing alternative industry called "contemporary Christian music."

The $100 million in Christian record sales this year are still small compared with the $4 billion secular market.But the Christian record industry is convinced that there is a huge untapped audience for "positive pop," and they may be right. A recent Gallup survey reported that 19 percent of Americans (41 million people) identified themselves as born-again Christians. Arbitron estimates that 30 million listen to religious programming at some time during each week.

So it's not surprising that in the last few years Christian record companies like World (owned by the ABC network), Sparrow, Light, Savoy, Lamb and Lion, and Songbird (owned by MCA/Universal) have begun to adopt secular marketing techniques.

In broadcasting, many Christian radio stations have begun to minimize sermons and maximize music. In recording, the increasing flow of Christian albums reflects bigger budgets and a move to pop professionalism countering the sincere amateurism that marked the early years of the music. (The much-publicized born-again experiences of Bob Dylan, Donna Summer, Al Green and B.J. Thomas haven't hurt.) And in promotion, there have been moves into the secular marketplace, and attempts to reach the majority of Christians with in-store appearances, T-shirts, video clips, buttons, posters and contests.

"From all I understand from reading the Bible," says John Styll, editor and publisher of Contemporary Christian Music magazine, a glossy hybrid of Rolling Stone and Billboard, "we Christians are here in the world as it is, with all the problems, and we're supposed to take the gospel to those around us. If we keep trying to bottle it up and hide it in our own safe Christian closets, then we seem to be disobeying scriptures."

Record World, one of the top music trade papers, now has separate charts for white "Contemporary and Inspirational Gospel" (acts like Amy Grant, the Imperials, Evie Tornquist-Karlsson, Don Fransisco and John Michael Talbot) and black "Soul and Spiritual Gospel" (Caesar, the Hawkins Family, James Cleveland, Myrna Summers, Al Green and numerous choirs and quartets). Most of these names will be unfamiliar to secular ears, but in the Christian market each can sell 200,000 to 400,000 albums -- a fact in which the record industry is suddenly interested.

"Many people who listen to Top 40 radio also go to church on Sunday," says Don Kline, director of marketing for the 15 Christian record companies who operate as the Benson Co. "If they knew there was such a thing as music for them, they would be encouraged about it."

"Ten years ago, there wasn't any product to listen to," says Styll. "There weren't any good records, and now there are. The product itself has gotten better, as has the industry's ability to market the product. There would have been a market 10 years ago if there'd been a product."

The traditions of Christian music are as old as the country, and the form is still dominated by hymns and gospel music -- both the vibrant black tradition and the more staid country and bluegrass varieties. Recently, however, a controversial alternative has arisen: contemporary Christian music (CCM), which uses secular methodology with a spiritual message. It's the fastest growing trend on Christian radio.

The controversies are centered on several issues. One of the major ones concerns crossover into the secular marketplace: "To cross over, you've got to take the Cross over," says one conservative observer, and many in the industry fear that the move will shift the role of the performer from ministry to entertainment.

But, "If we want to communicate, we have to speak the language of those we want to reach," says Styll. "The record companies realize they're dealing with a commercial product and they've got to consider the entertainment value of the record. The message may be great but unless the framework is well executed, people aren't going to listen to it."

Historically, a major drawback for much Christian music has been its tendency to biblically sound but simplistic lyrics and bland melodies, what B.J. Thomas has referred to as "Christian pop." That is changing as the demographic guidelines move toward young Christians who grew up in the rock era. Producers like Chris Christian and Michael Omartian (who produced the multi-platinum Christopher Cross album on the secular side) have revolutionized the studio approach to CCM, and the only difference between much contemporary Christian music and what one would hear on Top-40 or Middle of the Road pop stations is the message.

One representative example is Evie Tornquist's popular soft-rock rendering of "The Mirror" by Ron and Carol Harris: "You've heard of the Truth, heard of His message/Shouldn't that turn you around?/Could you have missed it, not understood it?/Do you know what you have found?/So mirror mirror on the wall/I know who is Lord of all/Just let me see Him every day/For me, that is the only way."

Despite its new appeal, CCM is meeting some resistance in both secular and Christian radio. "Gospel images evoke Mahalia Jackson or Rev. James Cleveland, not [CCMwriters] Kelly Livgren [of Kansas and author of "Dust in the Wind"] or Joe English [former drummer for Wings]," says Styll.

If a song is on a religious label, most commercial radio programmers won't even listen. Scott Shannon, program director of WPGC, says "many radio stations feel they have no right to impose religious views on our audience. Also, it's not what our listeners want to hear. That's why we don't play country music, either, unless a record becomes popular to the masses."

Compounding the problem, the tradition on many of the 1,400 Christian radio stations around the country has been uncreative programming; 36 percent of air time has been given to preaching and teaching, with much of that being devoted to fund raising, which in turn is used to purchase more air time. But now a new breed of executives -- many born again and almost all raised in the era of progressive radio -- has started to ease Christian radio into the mainstream.

KBRT, a Los Angeles station whose signal reaches up to Santa Barbara and down to the Mexican border, went "unequivocally music" six months ago. "We sound like any other good station," says general manager Bill Woods. "You can't build audiences a little here, a little there. We are now professionally programmed. Advertisers can bank on it and put their money in the station." Some stations, like KQLH in San Bernadino, are half and half, mixing secular and Christian music; KQLH even carries the Dodgers' games.

Of the eight local stations which carry a substancial amount of Christian music, WCTN (AM 95) and WDON (AM 1540) are the only one which play much CCM. WCTN program director John Vogt says, "Our music is light contemporary, bright middle of the road, that's where we'd like to fit in. It provides the potential for reaching the highest number of people with the Lord."

WYCB (1340 AM) programs a black and white mixture with emphasis on "inspirational music," with WUST (1120 AM) maintaining the black gospel tradition. WGTS (91.9 FM) programs "inspirational/sacred" with a bit of classical thrown in. Local observers desribe Washington Christian radio stations as deeply conservative, years behind stations on the West Coast, Southwest and Midwest -- where CCM programming is strongest.

Local Christian performers who garner black airplay include Myrna Summers, Andrew Rowe and the D.C. Choral Ensemble and The Brothers, while the Capital City Singers (who contemporized their name from The 150th Psalm) recently signed a contract with Word, the largest Christian label in the country. On the White side, The Carpenter's Tools and Scott Wesley Brown are the best known performers from the area.

Television, too, is part of the Christian music boom. Many observers credit the "electric church" for the evangelic tide rising in the nation today, and programs such as "The PTL Club" (with 200 network affiliates and 3,000 cable subscribers) and the "700 Club" are Christian equivalents of the "Tonight" show. Appearances of mainstream acts on these shows result in increased album sales; but perhaps more important, they convey approval of performers' lifestyles for extremely demanding (but also extremely loyal) Christian audiences.

The life behind the music is "extremely important," says Benson's Kline. "If the life style of the artist is not consistent with the message on the record, we have a serious problem. Many contracts have a clause about consistency of life style, that the principles must be held dear or the contract will be terminated."

Most observers agree that if Christian music is to grow as an industry, it must find greater radio acceptance, improve its product and take advantage of chains like Sears, Woolco, K-Mart and other key retail outlets which have recently joined secular record stores in the stocking of Christian music. Although black gospel has always been a part of the secular marketplace, 80 percent of CCM is sold through the 6,000 Christian bookstores -- which concentrate on books and attract only a tiny segment of public. Most Christian record companies want to see their product flow into the same channels as secular offerings, and so they've adopted many of the same marketing methods.

"Business is a world system, not a Christian system," says one pragmatist. "There's no such thing as Christian business, only good or bad business." The increased revenues of the last few years are just now allowing creative techniques, such as using independent promo men and marketing advisers, mobiles, giveaways, consumer contests. But the bottom line, everyone agrees, is not money. Although the format may have shifted from "Make a joyful noise" to "Play skillfully unto the Lord," the message is more important than the medium.

"Christian music has an inherent higher purpose than just entertainment," says Kline of the Benson Co. "Moving out of the church and out on the street seemed an unholy situation to many fundamentalists, but religious expression need not be confined to church. Our primary business is the spreading of the gospel. In order to do it, we must also function as a businiess."

John Styll points out that "Christians are serious about impacting today's society with good music that represents a positive value system -- you could also subsitute the word 'Christian' for positive. They're taking the talent they have to counteract a lot of the negative value they feel exists in much of today's music. Music induces so many different things: they're hoping to induce people to move in a direction toward Christ."