Samuel S. Siegel, 74-year-old French-born Jew, stood in the corridor outside a courtroom here today and glared at a droop-shouldered young man in a Nazi uniform.

"Look at me, you bastard" Siegel shouted at the self-styled storm trooper. "I'd like to crack your skull. That's the only way to deal with a snake. Seven of my cousins were murdered by you bastards."

The man in the brown shirt, Frank Collin, 32, glared back unflinchingly, but said nothing.

Collin is an unlikely Nazi. His family name was changed to Collin from Cohn. During World War II, his father was imprisoned for three months in Hitler's concentration camp at Dachau.

Represented by a Jewish lawyer provided by the American Civil Leverties Union, Collin was in court today trying to fend off legal efforts to block him from leading a Nazi march in the heavily Jewish Chicago suburb of Skokie.

He had hoped to march his 11-member National Socialist Party of America into Skokie on July 4, but postponed the march pending the outcome of his legal battles.

Skokie officials contend that a Nazi march in the village, which has 70,000 residents and nine synagogues, would arouse strong passions and perhaps lead to violence.

Rabbi Neil Brief of the Nile's Township Jerwish congregation, one of the Skokie synagogues, says the grass-roots reaction against the march is comparable to the reaction against the 1972 Munich massacre of Israeli athletes and the 1973 Yom Kippur war.

More that 700 Skokie resident turned out Tueday night at Rabbi Brief's synagogue for a panel on the march. The panel included David Hamlin, director of the Illinois ACLU, whose presentation was interrupted repeatedly by jeers from the audience.

David Goldberger, the Jewish ACLU attorney who has handled freedom-of-speech cases for Collin for seven years, says he has become used to being called "traitor" by strangers who approach him on the street.

When plans for the march first became known in April, the village hastily passed an ordinance prohibiting marches by persons wearing military-style uniforms, such as Collin's group wears.

Armed with the ordinance the village then obtained a circuit court injunction blocking the march.

Apparently fearful that as a result of Supreme Court action the injunction might be lifted next week, the Anti-Defamation League and other Jewish organizations are financing a private class-action suit on behalf of Skokie residents who are survivors of Nazi concentration camps.

Anti-Defamation League attorney Jerome H. Torshen told circuit court Judge Archibald J. Carey Jr. that the evidence he will present in support of the complaint will be "as obscene and horrendous as any ever presented in a courtroom in this city." A hearing was set for July 11.

The Chicago Association of Reform Rabbis called for all "legal means to prevent this march." It said that "The physical safety of American citizens takes precedence over issues of free speech."

Aryeh Neier, the national director of the ACLU, lamented that so much of the Illinois ACLU's time has been spent defending Collin.

"As a refugee of Nazi Germany, I find the passage of many years has not greatly subdued my own emotional response to the Nazis," Neier said. "But the obnoxious views of this group hardly seem to me to justify efforts by public agencies to emulate the actions of the Nazi government in Germany. In truth, it is not the Nazis who monopolize our time. It is public officials who think they are entitled to pick and choose when to comply with the requirement of the United States Constitution."

The first injunction was issued April 28 by Circuit Court Judge Joseph M. Wosik after lawyers for the village argued that the march was likely to lead to violence.

The ACLU immediately appealed to the Illinois appellate Court, which refused to treat the matter as an emergency. Under normal court procedures, it would have taken months or even years to decide the appeal.

As a result, the ACLU appealed to the U.S. Supreme Court, which on June 16 ruled that, because the issue involved freedom of expression, the Illinois court should either lift the ban or expedite the appeal.

In response, the Illinois court left the injunction in effect and set oral arguments on the case for July 8 - four days after the planned march.

Collin said he would obey the injunction, but said he is confident that he will win or appeal and that Nazis will march legally in Skokies.