Meeting in the wake of the inauguration of the president whose election they characterized as "a victory for God," about 2,500 evangelical Christian leaders gathered here this week to praise God and develop future strategy for turning the nation back to God.

The five-day gathering at the Sheraton Washington Hotel brought together the National Association of Evangelicals and the National Religious Broadcasters, two groups of the most influential leaders of the religious movement, which includes 40 million to 50 million born-again Americans.

Speaker after speaker portrayed the '80s as "the decade of the evangelicals," a boom time for conservatives generally and particularly for those concerned with a return to traditional morality.

The sleeping giant that has lain prostrate across America is beginning to wake itself," said the Rev. D. James Kennedy of Coral Ridge, Fla. "Believers in a living God are beginning to assert their spiritual rights," said Kennedy, whose church was a favorite of former President Richard Nixon when he visited his Florida White House.

"The '80s is the decade in which this country is going to have a moral rebirth," said the Rev. Jerry Falwell, founder of Moral Majority and pastor of the 18,000-member Liberty Baptist Church in Lynchburg, Va.

Evangelist Billy Graham, whom the religious broadcasters honored by inducting into their Hall of Fame, was optimistic, too, but struck a note of caution. Noting the "high expectation in the country" that a new administration will turn the country around, Graham said, "only God can do that."

The involvement of evangelicals -- or, as Falwell prefers to call them, Christian fundamentalists -- in poitics was one of the themes at the hundreds of speeches, workshops and discussions. Religious Roundtable, one of a number of groups of the so-called New Christian Right, conducted a five-hour speaking marathon on Tuesday to evaluate their role both in the past and the future.

Speaker after speaker portrayed the election of Ronald Reagan -- in which substantial numbers of theologically and politically conservative Christians played a larger role than ever before -- as not only the answer to their prayers but the judgment of God.

"It was Jesus that gave us this victory in November," said Bobbie James, wife of the governor of Alabama and a popular figure in born-again circles. "God in his mercy heard the prayers of Christians all over this country . . . perhaps all over the world."

James, who said she spends "most of my time in the prayer closet, which is where women belong, maybe," interpreted the release of the hostages after 444 days of captivity as special evidence that God is smiling on America. "I looked up what [the number] 444 means" in traditional numerology, she said, and concluded from her calculations that it signifies "a new beginning. So I believe God has intervened in American history."

Dr. Mildred Jefferson, an antiabortion crusader, proclaimed to sustained applause that the November election was "a victory for belief, a victory for faith, a victory for God."

Last July, Reagan traveled to the widely publicized National Convocation in Dallas conducted by the Religious Roundtable, where he received the blessing of several thousand fundamentalist leaders. But as president he did not respond to the invitation to appear at the sessions here this week, although both Gerald Ford and Jimmy Carter have appeared before the religious broadcasters' conventions while they were in the White House.

There were some expressions of disappointment both because Reagan did not show up and because of what the religious leaders perceive as his failure to pay political debts with appointments to his administration from the religious right.

"I know a lot of you are asking why there are no Christians in [appointive] public office," said the Rev. Robert Billings, who resigned his leadership post with Moral Majority to campaign for Reagan. Billings has said privately that he had hoped for an appointment to the White House staff as liaison for religious groups, a post that the Reagan administration has indicated it would not fill.

"There are a lot of things going on behind the scenes . . . there are a lot of good people being put into positions, not at the Cabinet level but behind the scenes -- the kind of people that love our ways," Billings said. Billings and other religious leaders generally tried to smooth over their disappointment at not being included in the Reagan administration.

But Howard Phillips, national director of the Conservative Caucus, was more forthright, reeling off a list of top appointees of whom conservatives disapprove. The list included Terrell Bell as Education secretary (". . . a slap in the face of everybody in this room"); Caspar Weinberger as Defense secretary; Frank Carlucci as Weinberger's deput (". . . I don't know what he's doing but I know I don't like it"); and Donald Regan as Treasury secretary.

The new Christian right, criticized during last fall's election campaign for its religious and ethnic exclusivity, seemed to be reaching out for new coalitions as the parade of speakers Tuesday included an Orthodox rabbi and three black clergyman.

Each of the black ministers denounced welfare programs. The Rev. Charles McKinney, 26, of Monroe, La., told the gathering that "the greatest thing God ever did for blacks in this country was to send some white men in ships to Africa and bring us back to this country so that we could know Jesus Christ."

McKinney said his family survived with the aid of food stamps when he was a child growing up on a subsistence farm in the rural South. "I am the product of the food stamp program . . . but there are a lot of people [receiving government assistance] who don't need it. . . The welfare system has done more to harm my people than slavery ever did," McKinney said. "If you were in slavery, with chains on your feet . . . you could still look up and ask the Lord Jesus Christ to save your soul. . . ."

The overwhelmingly white audience gave McKinney a standing ovation.

The bearded Orthodox rabbi, Abraham Hecht, wearing a black yarmulka, told the group in ringing tones that secularism in this country was the dangerous equivalent for the "organized religion" of communism in the Soviet Union and China and fascism in some parts of Latin America.

"We represent the majority of the American people who are God-fearing, taxpaying citizens of the greatest country on earth," the rabbi said. "God bless America!"

In the wake of controversy stirred up last summer when an evangelical leader said that God does not hear the prayers of Jews, evangelicals here seemed to be going out of their way to mend relations with the Jewish community. "I'm a fundamentalist [Christian]," said Falwell, "but I believe in a pluralistic America. This country belongs to the Hebrew Americans, the Mormon Americans, black Americans, white Americans."

Earlier at a press conference Falwell denounced anti-Semitism and said "every religious leader has the obligation from God to preach and pray and work to the end that we put an end to hate groups like the Nazis and the Ku Klux Klan." Most fundamentalist "Bible-believing Christians are very pro-Israel and pro-Jews because we believe in the Bible," Falwell said. He said that fundamentalists are "the best friend the Jews has. . . There is not one living anti-Semite in the Bible-believing church in America."

Falwell said that anti-Semitism is increasing in the United States and added that some of it "is a backlash at us [evangelical/fundamentalist Christians]. They see Reagan and they see us. They see that and they think that America is going to become unswervingly pro-Israel."

At his press conference the radio preacher said he was careful to observe strict separation of church and state. "I never wrap the cross in the flag," he said.

The press conference followed a congressional breakfast at which about 2,300 persons paid $22 each to hear Falwell. At each place in the ballroom was a packet of material promoting Falwell's enterprises. The packet included a four-color booklet about Falwell's "I Love America" rally. The entire back cover was a photograph of a well-worn American flag draped over a cross.

A human life amendment appeared to have the highest priority for the Religious Roundtable participants, closely followed by a call to establish more Christian schools. The Rev. Don Howard of Garland, Tex., said that "the two greatest influences in the destruction of our families are television and government education."

Calling the campaign for the restoration of prayer in public schools "a Bandaid on a cancer," Howard asserted that he would not want "an unsafe teacher teaching my child the Bible. . . . The safe thing is to get the kids out of public schools" and into Christian schools.

Graham, who made only a characteristically brief comment about politics, had some gently chastening words for religious broadcasters in his banquet address. He warned particularly against being seduced by success.

"When success becomes the goal, then we may fall into the trap of using any means to get it," he said. "Instead of trusting God to supply our financial needs, we may rely on a sophisticated direct mail campaign, give-aways or an advertising agency with a proven track record."

He added that religious broadcasters "need God's wisdom to avoid the pitfalls of depending on gimmicks and on high-pressure professional fundraising tactics as we seek to accomplish God's work."

Some critics of Graham have contended that his own organization not only uses sophisticated direct mail techniques at his Minneapolis headquarters but also retains a commercial advertising agency.

Graham also appealed to fellow broadcasters for full financial disclosure, a practice his organization has followed in the wake of criticism several years ago about an unpublicized fund.