Carrying signs saying things like "ERA Is Not the Way," and "I'm Woman/I Might Be Strong But I'll Stay Where I Belong," hundreds of people opposed to the Equal Rights Amendment descended on the state Capitol here yesterday to lobby legislators.

The number of demonstrators was difficult to determine since the group was never in one place at the same time. Unofficial estimates of the largely female crowd ranged from 1,000 to 4,500. Anti-ERA leaders said the demonstration was neither a rally nor a march but a show of grass roots opposition organized on short notice.

The effort, coming two days after a Labor-sponsored rally here attended by at least 3,000, was a counterskirmish in the escalating war over the ERA. Many legislators are becoming weary of lobbying by both sides and say that much of it is futile since just about everyone is fixed in his or her position.

Indeed, there is evidence that this battle is becoming a paper war of press releases and coordinated letter writing campaigns, with each side claiming to be presenting "the facts" and to represent the majority of Virginians.

Just as the Labor-sponsored rally utilized its organizations to produce busloads of ERA supporters, numerous churches marshaled their forces to oppose the proposed constitutional amendment. The Rev. Rod Bell of the Tabernacle Baptist Church in Virginia Beach, for example, announced from the pulpit the "need for us to go" and bused in 500 people alone.

"The fundamentalists have never been active in the political arena," he said. "We have to get active. We're organizing in every state. We have a constitutency of over 250,000. "Bell said the Christian school affiliated with his church was closed yesterday so that all of his 30 teachers could come to Richmond, and that 10 of the church's buses were used to bring people here. The use of other buses was donated, he said.

The "Stoppies," as the ERA proponents have labeled them, gathered in a church hall opposite the Capitol and in a public hearing room in the General Assembly office building to hear legislators who oppose the ERA, and filled the halls of the Capitol and the office building to buttonhole other legislators. They were instructed to be "decorous" and well behaved unlike the ERA supporters who they claim are obnoxious and rude.

The opponents intend the ERA is vague and thus interpretation of its would be left up to the courts, which are not as accountable to the people as legislators. They also say it would destroy family life by allowing homosexuals more privileges, forcing women to be drafted into the military, and eliminating special protections for women.

"I just think it is the wrong mechanism for change," said Kathryn K. Murray of Norfolk. "I think it would be better to deal with problems of discrimination with specific legislation. Putting it in the hands of the courts gives us less access to the process," she continued, adding in an aside, "That'sethe first time I've ever said that publicly."

Both sides try to deflate the credibility of the other by shows of strength.

For example, Del Vincent F. Callahan (R-Fairax), an ERA supporter for the five years it has been an issue in the General Assembly, said he has received more mail on the ERA than any other issue. As of yesterday afternoon he had in his office 61 letters, including two identical ones from the same couple, and four mailgrams against the ERA, and 66 forms from constituents who came to Richmond Sunday to attend the pro-ERA rally.

The frustrating nature of the arguments was illustrated yesterday when at one point freshman Del. Martin H. Perper (R-Fairfax), also an ERA supporter, was surrounded by about 75 young people he had agreed to argue with. "The ERA is against everything our country stands for!" shouted one young man. "Well I think it represents everything our country stands for," Perper answered.

Gary Lambert, 18, came with a church group from Norfolk. One reason he is against the ERA, he said, is that he was told in a church newsletter that if it passes he would have to pay twice as much in taxes when he gets married in June.When informed that if his wife earned no income he would not have to pay taxes on it, he said he was nonethless opposed to the ERA.

"It's a direct sin against God," he said. He quoted the Bible, the second chapter of Timothy, to support his position: "Let the women learn in silence with all subjection."

The two sides in this issues are even arguing over whose side God is on. A press release put out by proponents opened as follows: Monday quoting Christians in support of the ERA "'Christ was the first feminist,' said Lee Pemberton of Christ Church Episcopal in Pulaski."

And the pastor of the church hat rented a hall to ERA opponents yesterday felt compelled to send a notice to members of the General Assembly that "any legitimate organization can request the rental of St. Paul's Parish House for meeting purposes," but, continued the Rev. Craig Biddle III, he personally supported the ERA. "After considerable study of the state of women in the New Testament, I am convinced that Jesus was deeply concerned about improving the status of women in his male-oriented society."

STOP-ERA leader Alyse O'Neill of Alexandria said the turnout was unexpected and gratifying, and that unlike the ERA proponents who are interested in just that one issue, she hoped to capitalize on the newly politically active people who have become involved in the anti-ERA campaign to work on other issues. This hope was echoed by John T. Dolan, director of the National Conservative Political Action Acommittee, which he said plans to mount an anti-ERA campaign through its Virginia arm and develop what he said is a blossiming conservative constituency.