On one level, the blue-ribbon civil rights audience, listening to Vernon Jordan last night, was jubilant over the Supreme Court ruling that the government should withhold tax benefits from private schools that practice racial discrimination.

When William T. Coleman Jr., the attorney who argued the case that involved Bob Jones University and Goldsboro Christian Schools, entered the banquet hall, he received spirited handshakes and hugs, the Washington three-piece-suit community's version of bouquets of red roses. The reserved Coleman, a former secretary of transportation, moved through the crowd with a smile. "I was glad I helped the court come to the right decision," he said. Later he got a standing ovation.

But on another level, the supporters of the NAACP Legal Defense and Educational Fund Inc. were fuming over what some see as the Reagan administration's "packing" of the U.S. Commission on Civil Rights and other signs that the clock is turning back on racial progress.

Jordan, the former National Urban League president and main speaker at the fund's annual dinner last, termed the administration "an unmitigated disaster," called for the resignation of William Bradford Reynolds, the assistant attorney general for civil rights, and came close to calling President Reagan a liar.

Addressing Reynolds' recent speech on the merits of affirmative action, Jordan told the Capital Hilton crowd of about 400, "If he insists upon going against the grain of the national will, the laws and the court decisions he is bound to enforce, then he should resign.

"But what of his arguments? Is it true, that 'the use of race in the distribution of limited economic and education resources has regrettably led to the creation of a kind of racial spoils system in America.' Now, it is hard for me to figure that one out. A racial spoils system? For blacks in America? What in the world is he talking about? Does he mean the black share of poverty that's up to a third of all black families and still climbing thanks to Reaganomics? Does he mean the higher black share of unemployment?"

The administration, said Jordan, "is a crew that lies, shamelessly. The president himself goes around the country claiming that poverty rose during the Great Society years, while the government's own statistics show that the percentage of poor people was cut by 50 percent in the 1960s."

Joining in Jordan's warnings that the fight to end discrimination is just as intense as the days of the Brown school desegregation decision and the Little Rock school integration battle, were Jack Greenberg, the fund's director; Wiley Branton, dean of the Howard University Law School, and Robert Nathan, cochairman of the local fund committee.

Greenberg expressed concern over yesterday's nominations to the civil rights commission of three Democrats who share Reagan's opposition to racial quotas. He said if the three nominees receive Senate approval, it "signals the end of the commission as an influence in American life. This commission-packing plan with people of his own ideological position is not within the range of what the country sees as civil rights views."

Maudine Cooper, director of the Washington office of the National Urban League, said, "It is not so much the nominees, but the president misunderstands that this is a bipartisan, independent agency. He is confused. The agency will lose whatever credibility it has."

But the Supreme Court, reminded Branton, who played the chief justice in Coleman's dry-run of the arguments on the tax exemption case, remains a channel. "It's comforting to know the court is still there and right on some basic issues."