Leaders of Congress expressed relief last night that the tortuous investigation of Bert Lance's financial affairs had finally ended, and they applauded his decision to resign as a contribution to the national interest.

On both sides of the Capitol, there was considerable agreement that President Carter's stature, while surely diminished for the moment, is recoverable over the long haul.

Some senators and representatives turned their anger toward the press, warning darkly of media "festivals" that could discourage talented men and women in the private sector from government service.

But, for the most part, the reaction on Capitol Hill was that it would have been a mistake for Lance to remain as director of the Office of Management and Budget.

Senate Majority Leader Robert C. Byrd (D-W. Va.) said, "The nation cannot afford to have as director of the Office of Management and Budget a man whose personal problems are so great that they detract from the performance of his duties."

Lance's principal defender during the hearings of the Senate Governmental Affairs Committee, Sen. Samm Nunn (D-Ga.), praised Lance's courage, but coupled it with a warning that society's principle of the presumption of innocence had been eroded.

"With five government agencies probing into the affairs of Bert Lance, with hundreds of bureaucrats stumbling over themselves to see and possibly leak information on Bert Lance, and with scores of investigative reporters nipping at his heels, it becomes clear that his important job at OMB would have become difficult to perform," Nunn said.

The resignation had reverberations off Capitol Hill as well. The midafternoon announcement that Carter had postponed his scheduled news conference from 3 p.m. to 5 p.m. sent a tremor along Wall Street, and prices on the New York Stock Exchange tumbled 11 points in the last hour, to the lowest closing level since Dec. 22, 1975.

Fiscal conservatives in the Senate including Republicans, said that while they respected Lance's ability, they doubted whether he could have carried on any longer.

"I do think Lance was a major force for fiscal conservatism, but his effectiveness was pretty well vitiated and, despite what the President said, he wasn't as clean as a hound's tooth," said Sen. Clifford P. Hansen (R-Wyo.).

Sen. Barry Goldwater (R-Ariz), said, "I have respect for his business ability [but] I don't think he made the right judgements at times."

Goldwater said he was fearful of a proliferation of televised hearings into the morality of public officeholders, adding, "No one can withstand that kind of scrutiny."

Sen. James B. Allen (D-Ala.), who called Lance a "force for fiscal scanty," was among those who bitterly criticized the news media's role in the Lance affair.

Allen said he was 'apprehensive of the great power of the media to influence the course and direction of government." He added, "I don't know who their guns will be turned on next . . . They've gotten his scalp."

Sen. Thomas F. Eagleton (D-Mo), whose emotional defense of Lance hgihlihted some sessions of the Senate hearings, criticized recurring news media disclosures as "excessvie" and said he was offended by comments made during the hearing by Sen. Charles H. Percy (R-III).

"When you hear a senior accusing a United States official of being a tax evader, you ought to be offended, and I was."

For his part, Percy said last night that he "asked the questions that had to be asked." He said he felt certain that if Lance were now to seek confirmation, he would not be [WORD ILLEGIBLE] by that committee."

Depending on their political [WORD ILLEGIBLE] some senators called for further inquiries into Lance, or a [WORD ILLEGIBLE] on debate on the subject.

Sen. Bob Dale (R-Kan), said [WORD ILLEGIBLE] allegations should be pursued [WORD ILLEGIBLE] the public will know the truth as they finaly did in Watergate." But Sen. Edward M. Kennedy (D-Mass.) said. "This matter should no longer be allowed to dominate the national dialogue."

In the House, Speaker Thomas P. O'Neill said his advise on what Lance should do was never solicited or offered adding that "These two fellows [Carter and Lance] were extremely close, and I felt it would be settled by them."

O'Neill said he felt at the conclusion of the Senate hearings that it was "inevitable" that Lance would resign "because the press would be continually on him." But he said of the resignation, "Overall, it probably was the best thing to do."

Rep. John B. Anderson "R-III.), chairman, said he doubted whether Lance ever would have been nominated if all the facts in the matter had been in the public domain last fall when Carter selected him.

While praising Lance's decision as serving the national interest, Anderson said he was "disturbed and surprised" by the President's statement that the caharges against Lance were erroneous.

"It seems by doing this he [Carter] seems to be prejudging an ongoing investigation by the Justice Department," Anderson said.

Rep. Henry S. Reuss (D-Wis.), chairman of the House Banking Committee, said he felt Lance " . . . has done the right thing . . . In an administration that prides itself on the highest standards, there wasn't anything else to do."

Rep. John J. Flynt Jr. (D-Ga.), chairman of the House ethics committee, said, "I think that it is one of which tragedies of the era through which we are passing that a man like Bert Lance could be charged, tried, convicted and executed by a lynch mob without being given his day in court."

Another Georgian, Gov. George Busbee, who narrowly beat Lance to gain inessmen from agreeing to serve said he "cannot help out believe that he massive overkill employed against Mr. Lance will prevent talented businessman form agreeing to serve in government in the future for fear that they will be harrassed and hounded out of office."

In Calhoun, Ga., Lance's hometown and the base for his fortune and his financial troubles, friends expressed sadness and bitterness.

"It's a horrible mistake . . . Without Bert Lance, Jimmy Carter wouldn't be in the Oval Office today," said Harbin King, a probate judge who said he had known Lance since he was a teenager.