As Louis Farrakhan prepared to speak to 15,000 people packed into a South Side armory here last weekend, a small woman with a booming voice, the Rev. Willie Barrow, a well-known community activist, said a few words about the feared, hated, admired and idolized man on her left.

"I'm here because, No. 1, I love my brother, minister Louis Farrakhan," she said. "The devil don't like it, Chicago don't like it, the world don't like it -- but we love it."

The crowd exploded into thunderous cheers the same way black audiences around the nation are cheering and turning out -- in increasing numbers and with increasing passion -- for Farrakhan.

In the last month alone, Farrakhan, whose religious group, the Nation of Islam, numbers 10,000, spoke to unusually large crowds in Detroit, Atlanta, Philadelphia and Houston.

Farrakhan burst on the national scene last year after he traveled to Syria with Jesse L. Jackson and helped to gain the release of U.S. airman Robert Goodman Jr. Later he was dropped from the Jackson campaign team after well-publicized statements saying Israel would have no peace "structured on injustice, thievery, lying and deceit using God's name to shield your dirty religion . . . , " and saying that although he was not proud of Adolf Hitler's evils, "Hitler was a very great man."

Even before the Jackson campaign, Farrakhan was a fixture in some elements of the black community as the most militant of a large group of aspiring black leaders. A follower of the late Elijah Muhammad, Farrakhan preaches black separatism.

He seemed to fade into the background after the Jackson campaign.

But where 300 was a large crowd for Farrakhan a year ago in Detroit, last month about 6,000 came to see him, according to police and newspaper reports. In Atlanta about 7,000 packed a hall and others stood outside chanting his name. There were another 7,000 in Philadelphia and 5,000 in Houston.

His resurgence appears due to a growing frustration and discontent among many black Americans in the aftermath of a presidential campaign in which they participated actively but in which most of their candidates lost and their issues and proposals were defeated.

His appeal apparently has crossed international boundaries. Blacks in South Africa, who booed Sen. Edward M. Kennedy (D-Mass.), told reporters the only American leader they wanted to hear was Farrakhan.

He is fascinating to many blacks even though he has been denounced as anti-Semitic. He is held in contempt in some quarters for pronouncing a reporter worthy of "death" for revealing that Jackson had referred to Jews as "Hymies."

He has been labeled a racist and a hateful man in statements by the president, the vice president, members of Congress and some black leaders. Jewish leaders called him a "hateful bigot." Walter F. Mondale, during the campaign, called his statements "venomous, bigoted and obscene," and called on Jackson to repudiate him.

Farrakhan said he knows his association with Libyan dictator Muammar Qaddafi -- who he allowed to speak to his national convention by satellite -- inflames Americans incensed by Qaddafi's financial support of terrorist groups.

His popularity among some blacks continues as he speaks of radical, anti-American leaders like Qaddafi and Iran's Ayatollah Ruhollah Khomeini as his "brothers in Islam." He told his followers a week ago Sunday -- and in a later interview with The Washington Post -- that he hopes to follow Khomeini's example by distributing cassette tapes of his speeches to increase his following. Khomeini used the tapes to spread his revolution in Iran.

"What am I saying that has people shook?" Farrakhan asked the packed armory last week. "What is it that I'm saying that engenders fear in the heart of our oppressors? Just to mention my name, it strikes terror in the hearts of some white people.

"Why is that?" he asked. "I am a very small man. I don't have much muscle mass. I am a humble man. I never -- hardly -- been in a fight in my life. Why are you so terrified at Farrakhan . . . . What do you fear? I know what you fear. You fear the ideas that I represent because my ideas from God and Mohammad mean the end of your world . . . .

"It is an act of mercy to white people that we end your world. Your world is killing you and all of humanity," he added to excited, feverish applause after explaining that he sees the white world as a place that has created nuclear arms, polluted the air and land, and enslaved people of color. "We must end your world and bring in a new world."

He regularly spurs blacks to defy whites, chastising black parents, for example, for "bringing up children to salute the conqueror's flag, to fight for the conqueror's freedom . . . while we as [black] men have not yet enjoyed the freedom that America claims to give her citizens . . . . "

In an interview recently, Farrakhan's tone was muted, even friendly.

He asked about Milton Coleman, the Washington Post reporter he condemned as worthy of "death," indicating he still feels the reporter was "wrong" but that "people bounce back," especially in the minds of blacks who have "suffered so much." He described Coleman as a "valuable brother."

This is in contrast to his statement in a radio address during the campaign that he was going to "make an example of Milton Coleman." He also said that "one day soon we will punish you with death," but said that he was not directing the comment to Coleman.

He said some black leaders are "bankrupt" of ideas and that he feels most of America's 29 million blacks are "not productive."

Farrakhan said his attraction for blacks is in his standing as a "strong, uncompromising voice among black people." There has been a need for that voice in the "hearts of black people," he said, since the death of Martin Luther King Jr., the assassination of Malcolm X -- who was shot down during a speech 20 years ago in New York -- and the death of Farrakhan's predecessor, Elijah Muhammad.

"And when I was on TV [last year] -- not for my good but to show me as this wild-eyed, radical, anti-Semite, crazy man -- black people saw through that and saw in me . . . a new champion for their hurt and so that helped to increase my popularity among the people."

A reporter asked Farrakhan about branding Judaism a "dirty religion." As a "righteous person," Farrakhan said, he could not condemn the "revealed word of God . . . as being dirty or from the gutter as the press said."

"One's religion is not what one preaches," he said. "One's religion is what one practices. Consequently, I said the state of Israel had not had any peace in 40 years, that's true, and I said the state of Israel will not have any peace, that is also true."

"And then I made mention that the name of God was used to shield a dirty religion -- and when I say dirty I mean the practice of displacing millions of people from their homeland. Is it clean or dirty to justify the displacing of people who lived in that area for thousands of years by an assumption that you are the chosen people of God with a right to that land? Is that clean or dirty?"

Farrakhan said as a "man of God" he condemned that action as well as U.S. involvement in helping Israel. Consequently, he said, he has been called an anti-Semite. He claims that is unfair.

"I do not hate Jews," he said. "Nor would I dare to hate a person because of the way they believe or the color of their skin. Hate is engendered by actions that are contrary to the laws of justice."

Farrakhan was reported at the time to have said that " . . . Israel had not had any peace in 40 years and she will never have any peace because there can be no peace structured on injustice, thievery, lying and deceit using God's name to shield your dirty religion or practices under his holy and righteous name . . . . " He also said that the nations that helped create Israel and now support Israel "are criminals in the sight of the Almighty God."

Hyman H. Bookbinder, Washington representative of the American Jewish Committee, described Farrakhan's statements as a "clumsy effort to get himself out of the hole he put himself in."

"This attempt to rationalize his use of the 'gutter' or 'dirty' word is really not different from what every anti-Semite from Hitler on down has done," Bookbinder said. "They can't attack the essence of Judaism, because they know Jesus was a Jew. So it's not Judaism that is attacked but what they allege is inappropriate behavior of Jews."

Farrakhan "is a hateful bigot and I don't know what else can be said," Bookbinder said.

The Post interview took place on the morning after Qaddafi, the Libyan dictator, addressed Farrakhan's "Savior's Day" convention through a satellite television hookup and urged black U.S. soldiers to leave the military and form their own army to fight for a separate black nation.

Farrakhan said he could not advise black soldiers to follow Qaddafi's advice.

Asked if the fear whites have of him does not hurt his chances to help the black cause among the wider population, Farrakhan said, "Fear starts the process of negotiation. That's why America, when she was sitting at the table with the Vietnamese, ordered bombings of the north . . . [so] fear is a necessary prerequisite in the mind of the slave-master to begin negotiating with the slave."

Farrakhan said he has not contributed to what he said are worsening race relations in the country. Racial polarization, he said, has been prompted by the clash of economic progress for the rich -- primarily whites -- with the sinking realization among middle-class whites that the recovery has bypassed them.

"When whites are not eating steak as often," he said, they become angry and blacks bear the brunt of that anger.

Farrakhan spoke approvingly of President Reagan. He said Reagan is on a par with Abraham Lincoln as a president trying to save the nation but faced with the core question of what to do about blacks.

"Mr. Reagan is facing the same dilemma," Farrakhan said, "saving America, and at the root of that is what to do with 30 to 40 million black people, most of whom are not productive."

The answer, Farrakhan said, is for blacks to become economically strong by starting companies to provide products that other blacks can buy with the estimated $190 billion that American blacks spend annually. Farrakhan said Jews, Arabs and now Orientals have set up stores in black communities and grown wealthy by "feeding" on the black economy. Now blacks must do the same, he said.

The Muslim leader has formed a company, POWER (People Organized to Work for Economic Renewal) to raise $5 million to get a company started to make and distribute household products to black consumers.

"The American people are sick and tired of the president giving, giving, giving their money away . . . , " he said, "to the poor and minorities. So the time, to me, is ripe for black people to organize a business . . . turning some of the $190 billion purchasing power back into our community to lift our own community up. That will better race relations because 30 to 40 million American blacks have become an intolerable burden on society."

As for other black leaders' complaints about Reagan, Farrakan agreed that the president could do more, as a former actor, to put himself in the shoes of people who recently had to "die to go to toilet" in this country.

"I think the president needs a deeper understanding," Farrakhan said. "But in my judgment he is correct that black leaders, in general, have not paid attention to the economic problems of our people and some black leaders are thinking only of lining their own pockets and not looking after the masses of the people. But certainly not all black leaders are like that. They are just bankrupt because they don't really know what to do to solve the problems of their people."