Senate Chaplain Richard C. Halverson frets about partisan strife on Capitol Hill--so much so that during the 1982 lame duck session he took his concern to the Senate floor.

"Humpty Dumpty sat on the wall," the Rev. Halverson reminded some of the nation's most powerful men and women in his invocation one morning. "Humpty Dumpty had a great fall. All the king's horses and all the king's men couldn't put Humpty Dumpty together again. Dear God, don't let the Senate come apart . . ."

A vaudeville performer before he entered the Presbyterian church, Halverson, 67, relishes the opportunity to zing his political parishioners with "relevant prayers." But he gets serious very quickly when asked what the $57,494-a-year Senate chaplain does in addition to giving his daily one-minute invocation.

"That's the only official required duty," he concedes, "but there's much more to the job of watching over this group."

Congress has hired preachers since its inception, but only in recent years have the two houses retained full-time chaplains. Last month, ruling on a Nebraska suit, the Supreme Court affirmed the constitutionality of legislatures hiring chaplains. The decision focused attention on Halverson and his $67,200-a-year House counterpart, the Rev. James Ford, though neither man will comment directly on the case.

"I do my work best by not being a defendant," says Ford, 52, a five-year veteran of the Hill.

Says Halverson, who arrived in 1981: "We're needed here."

The chaplains explain that their days are filled with building dedications and congressional prayer breakfasts, meetings with visiting foreign delegations and an occasional wedding or funeral.

Ford, who unlike Halverson wears a clerical collar, emphasizes that "a chaplain is on call at all times"--and for all sorts of crises.

For example, says Ford, when House Majority Leader Jim Wright recently had some friends up from Texas, they found themselves short on entertainment.

"They needed an extra harmonica player for a duet with Wright to play 'The Saints Go Marching In.' Well, I happen to play harmonica, and I was happy to join."

Most important of all, the chaplains agree, is their responsibility to minister to the steady stream of troubled souls who seek their advice on personal and political matters.

"I could write the most interesting book that will never be written," says Ford, 52, smiling. He says he has counseled representatives considering a run at the Senate and those running from trouble in the House.

His congregants' insecurities and improprieties, will, however, remain confidential.

Journalists "ask about specifics, Abscam and so on--what I said to people then," says Ford. "Those things are sacred, a trust. They can't be told by me or by any minister."

Halverson is equally tight-lipped about naming those who visit his cramped office in the Hart Senate Office Building, saying only that his parishioners fear terribly for their privacy.

"You remember what happened to Sen. Thomas Eagleton D-Mo. when he was running for vice president and word got out that he had had therapy," Halverson says. "I don't know that opponents would take advantage of it, but they're all sensitive to that type of thing."

In the 1950s, Halverson had a church in Hollywood that many movie stars attended, so he is especially sensitive to the pressures on "all people who live their lives in glass houses . . . They have a tendency to believe their own publicity--senators just like actors."

Sen. Mark Hatfield (R-Ore.) often consults with Halverson when they attend the weekly Senate prayer breakfast. "There are many times when a concerned, compassionate ear is important," says Hatfield. "I know there are many, especially staffers, who seek out his counsel."

Rep. Ted Weiss (D-N.Y.) praises Ford for being "quite sensitive to the fact that he represents all religions and denominations here." Weiss, a Jew, says Ford recently sought him out, "somewhat chagrined," after a fundamentalist Christian guest preacher delivered "a particularly strident prayer."

"He wanted to reassure me that the guy might be popular at home, in a parochial setting, but that he could not adjust well to another setting."

The chaplains received strong support from many members during the recent constitutional challenge before the Supreme Court. But the Rev. Robert Drinan, a former representative who is a Jesuit priest and now teaches law at Georgetown University, says "the presence of chaplains is not one of those pressing issues" in Congress.

"I myself don't feel strongly either way," adds Drinan. "I'm not sure it's all that important whether they're there or not."

Like many of their predecessors, Ford and Halverson had high political connections before they were asked to serve Congress. Halverson preached to many legislators at the Fourth Presbyterian Church in Bethesda for 23 years. Ford, a Lutheran, served at the pleasure of the president for 18 years as chaplain at West Point.

They say they have no desire to influence legislation, commenting only when asked and even then with considerable caution.

"I would say right away that I oppose abortion," says Halverson. "But I also believe very strongly that God endowed us with free will and the responsibility for free choice. I am not here to make up the senators' minds for them."

A chaplain's prayers, says Halverson, are "directed to God, not to the senators." Yet a careful listener cannot help noticing Halverson's efforts to frame worldly matters, such as security leaks, in a broader perspective.

"Lord God," he began one recent offering, "Thou art acquainted with all our ways. For Thee no plans are classified."

Halverson says he keeps in mind one political prayer that failed to enlighten a crucial listener. Preaching in the White House in 1969, while still a minister in Bethesda, he warned Richard Nixon of politicians "who take responsibility so seriously that they think they can do it all themselves, without God."

"That's where I felt, frankly, Richard Nixon was then," says Halverson. "I felt he didn't like it, didn't listen."

Could the whole Watergate cover-up have been prevented if Halverson had broken through to Nixon?

The pastor shrugs, then frowns. He says, "I often wish that somehow he had had more humility. It remains a good lesson."