As Rep. Edwin B. Forsythe (R-NJ) strode out of the House chamber recently, a soft-soken man who had been waiting in the hallway stepped up to him.

The lobbyist pulled a piece of paper from his pocket, handed it to Forsythe, and stood silently while the congressman read. The two men then exchanged a few words, Forsythe signed the paper, and handed it back.

The episode marked a new triumph for Edward Snyder, who had just enlisted another lawnmaker in the campaign against a bill seeking to revive military draft registration.

Snyder, who represents the Friends Committee on National Legislation, is one of about 100 men and women who form one of the more unusual special interest groups on Capitol Hill - the religious lobby.

While some of the religious lobbying is directed at obvious institutional interests - such as aid to parochial schools or Israel - many of the religious lobbyists spend most of their time on what they call "social justice issues."

They operate in many cases on shoestring budgets, in contrast to the well financed operations of lobbyists representing such organizations as the National Association of Manufacturers and the AFL-CIO.

While their secular colleagues can dangle the lure of junkets and speakers fees, one remarked, all that most religious lobbyists have to offer is a prayer that a reluctant lawmaker will see the error of his ways.

The religious lobbyists are the first to admit that they probably have a marginal influence on the course of legislation.

"I certainly know the church doesn't deliver the vote any more - not even the Catholics," says Jane Lieper, one of two representatives for the National Council of Churches."Every congressman knows that within any given church, you've got a whole spectrum of views."

All too often, laments Lieper, "the religious community is often on the losing side" on the major issues.

"But we're like David," she says in a reference to the biblical tale of David and Goliath, "with a little pebble in his hand.

"We're not here because we think we have a chance to succeed, but because we're faithful to the gospel."

The religious lobbyists justify their intervention in the processes of government as an up-to-date expression of religion's traditional concern for the needy on the one hand, and with the proclamation of ethical and moral values on the other.

"We think it's important to have a church set up a child-care center," said the Rev. J. Elliott Corbett of the United Methodist's Board of Church and Society.

"But if there are 5 million children needing care, and if we can affect the social policy on child care for the entire nation, that's a very significant opportunity," he added.

Others feel that lobbying is a form of preaching. "The churches' single most important role in Washington is to help people (in government) sort out the values that are implicit in the decisions that they make," said the Rev. Barry Lynn of the United Church of Christ, who is also a lawyer.

"We ought to be able to say to the government: 'you have done something wrong; you have chosen the wrong path to take,'" Lynn said.

He recalled an argument he had with Sen. Sam Nunn (D.-Ga.) over whether or not the United States should intervene in Saudi Arabia for petroleum, in which Lynn said he told the senator: "I don't want you to make the decision, to intervene and steal somebody's oil.' That's immoral. I'm not afraid to use that word. I think at out best that's what we ought to be doing."

The professional staffs of most of the religious lobbying groups here have only two or three full-time persons, which sharply limits the number of visits that can be made to members of Congress.

"We don't have the two things that seem to count most around here - money and votes," acknowledged Snyder. "But there are a considerable number of members of Congress who recognize that there are other considerations to be taken into account when casting their vote - moral and ethical and religious considerations," he said.

"You can only do half the job if you're not focusing your attention on educating your constituency," observed Snyder, who estimates that he divides his time "about 70-30" between education and lobbying. "And we do more actual lobbying than most church groups," he said.

The 70 percent of his time goes into production of monthly newsletters with progress reports on the course of bills the group is interested in, development of carefully researched background papers on the important issues, compiling up-to-date voting records of members of Congress on selected issues, and shuttling around the country to make speeches and conduct legislative seminars for Friends and other groups.

The education directed at the grass roots includes an emphasis on the fact that "a lot of members (of Congress) are spending a lot more time on weekends back in their district . . . We try to get our people to take a delegation and go to see them. I think that's a lot more effective" than for the professionals in Washington to try to track down the members here, Snyder said.

Rep. Robert Edgar (D-Pa.) says that is one of the reasons he gives high marks to the efforts of the Friends Committee. "They make sure that every six months some people from the district sit down with me when I'm back there." said Edgar. "That's much more effective than just getting a letter about what the head of the church believes."

Regligious lobbyists of all denominations alert their leadership to hearings on iissues in which that group is particularly interested and get either technical experts or ecclesiastical big wheels on the schedule to testify.

"Very often we get calls from the Hill (from congressional staffs) asking if we are interested in testifying," said Msgr. Francis Lally of the United States Conference of Catholic Bishops. The same is true of Protestant leaders.

To compensate for limitations of budget and manpower, religious lobbyists here have formed their own coalition, called the Washington Interfaith Staff Council. Currently 38 groups belong, though the number fluctuates as new coalitions within the larger coalition come together to deal with a particular issue - such as the draft - and older groups dissolve.

Membership includes Washington offices of the main Protestant bodies, several Catholic and Jewish groups as well as such groups as the Christian Scientists and the Metropolitan Community Church, which ministers primarily to homosexuals.

WISC has neither staff nor budget of its own. Nevertheless, the National Council of Churches' Lieper observes, "It's incredible how much glue there is." When an issue, such as the question of lifting sanctions against Zimbabwe/Rhodesia, comes up, she explained, "The call goes out: "Who can lobby on the 18th and 19th?'"

At the same time, drum up support among church members in the home districts of "swing" members of Congress - "to get the grass roots bishops to call," Lieper explains.

There is no way to fix a meaningful price tage on the cost of the operations of the religious lobby. Some offices perform a variety of functions in addition to lobbying. The United Methodist Board of Christian Social Concerns, for instance, has an executive staff of 15 - one of the largest in town. But in addition to legislative activity, the agency is a major division of the church and carries on a separate program of education, research and administration that is unrelated to legislative activities.

In other organizations, the department specifically charged with government liasion receives substantial help from other quarters. The current budget of the government liaison department of the National Conference of Catholic Bishops is $270,545. But the work of the five professionals who staff that department is frequently augmented by Conference experts in social development and peace, communication education, and pro-life activities, and individual bishops and cardinals who are called in to "give higher visibility" to issues with testimony before congressional committees.

Many religious lobbying organizations expand their effectiveness through the use of graduate students and others who spend anywhere from a summer to a year as interns, most often doing the kind of research that is the bedrock of effective lobbying. Such interns receive subsistence pay, or in some cases, nothing at all.

The Friends Committee on National Legislation, for example, currently sustains a professional staff or three, a secretarial and support staff, plus six interns (one is a Jesuit priest), with an annual budget of $330,000. That figure, incidentally, includes the salary of the staff member whose responsibility it is to raise the budget.

Of all the religious agencies involved in lobbying, only three are registered as lobbyists: the Friends Committee, as unofficial organization of Roman Catholic nuns called NETWORK, and a new right-wing group that was launched last month to counteract the influence of the more liberal churches, the Christian Voice, but which has yet to develop a track record.

Section 501C-3 of the Internal Revenue Service code provides that non-profit organizations, including religious ones, do not jeopardize their tax-exempt status so long as "no substantial part" of their activities is directed at "carrying on propaganda or otherwise attempting to influence legislation. . ."

The IRS has never sought to define "substantial" in that regulation. In the light of their total national programs, the relatively small lobbying efforts of church groups here have not prompted challenges of their tax-exempt status.

Although the religious lobby receives mixed reviews on its effectiveness, the National Council of Churches' Lieper says she is encouraged to continue to work because "so many votes are won by 2 or 3 per cent.

"Our effectiveness is mixed," said Rabbi David Saperstein, director of Reform Judaism's Washington office. "If the religious lobby disappeared today, it would not change the dynamics much."

Msgr. George Higgins of the United States Conference of Catholic Bishops and a veteran of the Washington scene, admitted that his inclination was to "underestimate rather than overestimate the effectiveness of the churchy lobby." But he, like many others, cited the civil rights battle of the 1960s as one in which the church, in coalition with other forces, made a difference. CAPTION:

Picture, Edward Snyder of Friends group, checks Congressional Record. By Margaret Thomas - The Washington Post