It's Saturday night and all the people at the Holy Land Spiritual Temple are decked out in their Sunday best.

Fans are flapping, hands are clapping and the music is humming, producing a sound big enough to draw a crowd off Florida Avenue.

Gospel music is on the bill at the Northeast church, courtesy of the Prodigal Sons, the Gospel Pearls and the Southern Gospel Singers. And the occasion is a fund-raiser for the seventh annual Southern Gospel Singers Festival scheduled for Saturday in Anacostia Park.

Preaching the gospel in four-part harmony turns few performers into millionaires, but the Southern Gospel Singers have a mission so important that they'll pay for it out of their own pockets. It's a musical mission, dedicated to bringing the message of hope and love to the people.

"Some people call it singing; we call it ministry," said founding member Cleophus Pointer.

Like other gospel groups in the city, "we pay to sing," said drummer Jonathan Shanks.

"It takes love," said Pointer, " 'cause there isn't any money in this deal."

It costs the Southerns $100 to send their music over the airwaves every Sunday at WUST-AM (1120), Washington's oldest all-gospel station, and, at 1,000 watts, the signal barely reaches the Capital Beltway.

Still, WUST reaches gospel lovers around the city, and the Southerns can usually count on full houses (or gyms, or school auditoriums) three nights a week.

The group gives about 150 performances a year, mostly benefits. Senior citizen groups, the heart transplant center at Howard University and the Fifth Street Block Club are some of the recipients.

The Southerns are the youngsters in a gospel scene where groups have stayed together for a generation or more. Local legends such as the Four Echoes and Martha Christmas and the Jubilees have been singing since the '40s, and the D.C. Harmoneers since the '50s.

At the fund-raiser, one of the singers cautioned members of the audience never to forget where they came from. The Southerns' roots were planted in Alabama 23 years ago and they don't forget it. "The year after we moved north, we heard our church needed air-conditioning. We went back one summer to do a benefit and we've been going back every year since," said Pointer.

Each of the 14 members of the Southerns spends 18 hours a week at music and 40 hours at jobs that support their music. They are microfilm technicians, government workers, truck drivers, and one, Antoine Glasco, a lead singer, will soon be a sixth grader.

The Southerns caught a glimpse of stardom in 1977 when their single "Tell Jesus" hit it big in the South. This summer they plan to release their first album, and Shanks, who doubles as public relations man for the group, is gearing up to peddle the album to gospel stations on the East Coast.

"You can't go anywhere if the DJs don't like you. And more than your music, they have to like you the person," he says.

Gospel music rarely makes the weekly Top 40 chart and its superstars don't make the cover of People magazine, but stand on any inner-city neighborhood corner on any given day and chances are that someone will be singing nearby.

Says city folklorist Michael Licht, "People don't realize how active it is. It's like holding hundreds of free concerts a year."

Licht, who signed on as the city's first folklorist in January, is working on the Gospel Survey Project for the D.C. Commission on the Arts and Humanities. Already he's documented more than 60 gospel groups not affiliated with any church.

"If you count the churches, and there are 500 black congregations in D.C., you can boost the number of groups singing gospel to more than 1,000, because every church has more than one choir. When you add it up, that's a lot of music," he said.

There will be a lot of music from 1 p.m. to sundown Saturday at the Southerns' citywide event with the D.C. Harmoneers, Mattie Johnson and the Stars of Faith and 11 other groups north of the pavilion and the U.S. Park Police station in Anacostia Park. Concertgoers can enjoy free hamburgers, hot dogs and cotton candy. Most of the food is donated and the rest bought at reduced rates from local merchants.

"I don't know how many people were there {last year}," said Viola Brown, who works with the group. "But I was handling the cotton candy and I had 1,500 cones. They were all gone by the end of the day."

The Southerns fest ran into some problems last year with the Potomac Riverfest celebration going on at the other end of the park. "The police blocked off the road to our event because they didn't know we were there," recalled Pointer. "Some of the people are elderly and they had to walk miles from the parking lot."

Brown says she expects parking to be a problem again. "But our people will are going to come anyway."

By the end of the evening, the audience at Holy Land Spiritual Temple was worn out but smiling. They had pooled $105 for the event, enough to pay for half the stage rental.

Coming up short doesn't bother the Southerns. They don't have time to dwell on what they don't have because there are benefits next week and the week after and the week after that. The Southerns practice what they preach: They're "gonna sing a brand new song when they get home."