Is a Christmas creche, with its sheep and donkeys and the Baby Jesus in the manger, a religious or a cultural symbol?

"Religious," said four out of five of the 280 Metro riders questioned yesterday morning by the Anti-Defamation League of B'nai B'rith.

ADL officials, in a press conference yesterday, released the results of their impromptu poll, using the figures to undergird their opposi- tion to the National Park Service's decision to include a nativity scene in its annual Christmas pageant.

The nativity scene has been absent from the annual Pageant of Peace ever since the U.S. District Court ruled in 1973 against including a creche in the government-sponsored Christmas pageant.

But, in a Pawtucket, R.I., case last March, the Supreme Court ruled that a nativity scene could be considered a cultural symbol, as is Santa Claus. So the Park Service acceded to pressures from a Northern Virginia group called Citizens for God and Country and made plans for a creche in its seasonal display.

The ADL has protested the action as both "insensitive to non-Christians" and as a violation of First Amendment guarantees of church-state separation.

"Eleven years ago the court said there should not be a creche . . . because it was a violation of the First Amendment," said Edward N. Leavy, regional director of the ADL.

Leavy said another case pending before the Supreme Court bears on the situation. In that case, the court has been asked to rule whether a private group can force the New York suburb of Scarsdale, which has a heavily Jewish population, to display a nativity scene on public land.

"We are shocked that an agency of the federal government has gone ahead with this before the Supreme Court has ruled" on the Scarsdale case, Leavy said.

The Rev. John Steinbruck of Luther Place Church, who was present at yesterday's press conference, said the pressures of Christian groups to force inclusion of a creche in the Park Service display tended to "denigrate" a religious symbol.

"It not only trivializes it, it serves the purposes only of those who want to Christianize America," Steinbruck said.