It was a Sunday of passionate sermons and songs, from early morning till on past midnight. Ministers sopped the sweat from their faces with handkerchiefs as their voices grew into harsh roars of glory. Listeners lifted their hands, palms cupped toward the pulpit as if to feel, for just a few seconds, the words breezing against them. Choir directors faced swaying walls of crimson or sky blue or cream, cutting the air with their arms to pull one rich echoing voice from 200 lungs.

At a convention of gospel musicians, you'd expect God to receive praise, and plenty of it. But when Mayor Marion Barry took the stage -- that was something.

"You read a lot about what's been happening here in Washington," he told several thousand members of the Gospel Music Workshop of America Sunday night. "A lot about the evidence, the alleged evidence that the prosecutor may have. But let me just tell you that God is a better lawyer."

Appreciative laughter and scattered applause rose inside the Washington Convention Center. The aisles were swirling with people taking snapshots. Then the mayor said, "I stand here as a living miracle to His mercy and His grace."

Two days after he was convicted on a misdemeanor count of cocaine possession, beating 13 other drug and perjury charges, and one day after he gave a speech calling upon the city to "forget about this trial ... let go, let go and heal," Barry issued this warning to his black audience:

"All is not well in our land. Satan and satanic forces are everywhere, trying to destroy all that which we've built up. Particularly if you're African American, you better watch out. Whether you have a PhD or no D, you better watch out. Whether you're a DS-15 or a DS-2, you better watch out."

The mayor's five-minute message provided a new understanding of his 10-week ordeal in U.S. District Court. To him, evidently, the trial was nothing less than a showdown between Satan and Almighty God.

The mayor's visit came near the end of the first full day of the 23rd annual convention of the GMWA, which has attracted 7,000 to 8,000 choir members and church musicians from across the country for a week of workshops devoted to making better gospel music.

Sunday was a day of welcome and worship. It was also a day for politics, as a fiery afternoon speech by Jesse Jackson brought rows of men and women, most dressed in white, to their feet. Jackson equated the District's lack of voting representatives in Congress with apartheid, saying, "If we could go to jail every day for a year to free South Africa, we can do the same thing to free D.C."

But the absence of the workshop's founder, the Rev. James Cleveland -- himself a legend of gospel music -- often made itself tangible.

"There is a weapon that is more powerful than any nuclear warfare. And I want to use it today on behalf of Reverend Cleveland," said the Rev. Xavier Naper of New York, beginning the afternoon's main sermon. "That is the weapon of prayer. {Don't worry} what the exact problem is. We serve a God that can fix anything." Voices swelled in affirmation.

Preacher after preacher summoned up prayers to help Cleveland in his time of illness, though none of them would say what was wrong with him.

The Rev. Norma Jean Pender, the convention publicist, said yesterday only that "he is ill" and in a Washington-area hospital. "At this point, it's not critical," she said. She hopes Cleveland will join the assembly in a few days, in time to oversee the biggest event of the annual workshop -- the recording of a double album by a 3,000-voice GMWA choir. "He may not be performing, but he will be there" for the Friday recording, Pender said.

Reached by phone last week at his Los Angeles home, Cleveland, 58, alluded to his health. "I'm not tired in the sense of the work. Physically tired, yes. But not tired in the sense of what has to be done," he said. With 12 gold or platinum albums and two Grammy awards to his credit, Cleveland said his purpose is "to perpetuate and upgrade the quality of gospel music for this generation and generations to come."

The Rev. Kenneth Ulmer of Los Angeles concluded a modest Sunday morning service with a request that might have seemed unnecessary, given that this is a convention of active church members. But "after 14 years in the ministry, and 35 years in music," Ulmer said to the small gathering, "I can tell you that plenty of people are going to Hell wearing choir robes."

He called for people who hadn't yet accepted Jesus Christ as their personal savior, or who weren't sure of their commitment, to step forward. This was more important, Ulmer said, than any songs that might be sung this week. More important than the embarrassment of coming forward at a convention of Christians.

A minute passed, then two minutes, as the minister continued to call for someone to take that bold step.

And when a thin young woman began walking slowly down the center aisle, the room was overcome with emotion. Ulmer stood with the woman, her head downturned, talking to her briefly before another minister pulled her aside.

Then, from up front, an older woman got up, turning to address the cheering audience with a deep, indescribable smile on her face. "That's my daughter, and I prayed!" she said, stepping robustly up the aisle, shaking her head and holding up a hand.

Vendors at the Gospel Music Workshop of America are offering gospel albums and tapes, sheet music, large jewelry, women's hats and the latest in bootleg Africanized Bart Simpson T-shirts. No kidding. Not even at a gospel convention can you escape the smug glare of a brown-faced Bart quoting M.C. Hammer: "You can't touch this."

Asked whether Bart T-shirts might clash with the theme of the convention, one vendor said, "This is just for the kids, really." Indeed, there are a number of young children to be found here. One little girl, in fact, happened to be at the vendor's stand, along with a woman and an imposing gentleman who said, "I don't mean to butt in. But how can it be contrary to our theme? We're black."

But Bart Simpson T-shirts, at a gathering of gospel musicians?

"We're still human, though," the gentleman said. The couple proceeded to ascertain the price of the T-shirts -- $10 a pop -- then moved along.

Just call it one of those goofy coincidences. Mayor Barry and his entourage entered the main hall of the Convention Center just as a soloist for D.C.'s Salvation Corporation choir was repeating the words "Give me one more chance."

It was around 8:40 p.m., an hour after the nightly musical service had begun. Choirs had registered earlier in the day to perform two songs each.

The mayor didn't speak right away. There was moderate applause and a few members of the audience stood as he ascended the stage. But Barry took a seat in front of the organ to the right, and held on to a program as the choral cavalcade continued. Occasionally he would leaf through the program or tap his feet to a song.

After maybe 10 minutes, Barry left his seat and moved to a back corner of the stage, where he stood and listened to more songs, sometimes allowing his knees to bounce with the rhythm.

But as the D.C. Mass Choir put forth its foot-stomping version of "Oh What a Friend We Have in Jesus," young choir director Cliff Jones, microphone in hand, was struck with an idea. He reached toward the mayor, beckoning him to center stage.

Barry smiled and lifted his hand in polite refusal.

Jones insisted, and slowly Barry left his corner. "We're gonna do a victory step!" Jones told him as the drummer kept up a relentless beat. With that, the choir director and the mayor strutted from the right side of the stage to the left.

"Say yeah!" Jones shouted, putting his mike to Barry's face.

Smiling and bouncing, Barry complied. "Yeah!"

"Victory!" shouted Jones.

"Victory!" echoed Barry.

Jones later explained that two weeks ago, Barry attended a service at the Israel Baptist Church in Northeast. "And I had told him before the service, I said, 'Yo, you've got the victory. All you have to do is believe that you've got the victory.' He said, 'I've got the victory.' We took a stroll down the aisle -- you know, we took a victory dance -- and after that, it was all she wrote. And I told him when he wins {the trial}, we're going to dance this thing off. We're going to dance downtown off. And we did it."

Barry was formally introduced to the audience by William C. Sims, the vice president of the Gospel Music Workshop of America, who had invited him to attend the convention. "A hero to all of us," announced Sims, a white-haired man who issued each syllable with solemnity. "A great man. A great mayor. And a man of God who can claim the victory! Ladies and gentleman, Mayor Harold Washington -- no."

Sims turned to Barry. Laughter filled the place. "Didn't I mess up!" Sims said, smiling as well. "Mayor Barry!"

Barry began by reciting the first verse of "Amazing Grace," as he had Saturday afternoon during his televised address from the Reeves Municipal Center.

"I'm here to tell you that God is able, and God does answer prayers," Barry said. "Do you believe it? Is God able? Is He able? If you believe God is able raise your hand, wave your hand! Say God is able! God is able!"

Barry said, "My God, my magnificent, majestic and almighty God, is a forgiving God, isn't he? A forgiving God." The audience applauded. "He came into this world not to save saints but to save sinners."

Barry invoked a moment of silence for the Rev. James Cleveland.

He garnered more applause after he made his "you better watch out" remarks, and said that unless black people "band together spiritually, economically, socially and politically, we're not going to make it here in America."

Shirley Berkely, head of the Washington chapter of the GMWA, said the mayor had delivered "excellent words." About Barry's "God is a better lawyer" line, she said, "Well, God is. He has fought many a battle in a courtroom. Even though the man manifests himself as an attorney, God still is the one who does the work. So I'd have to agree with him on that."

Special correspondent Hamil R. Harris contributed to this story.