After four days and more than 20 hours with Alexander M. Haig Jr. at the witness table, Senate confirmation hearings for the secretary of state-designate erupted with the emotion and anger of the watergate-era yesterday.

Haig, his voice occasionally rising in anger and falling in apparent dismay, clashed openly with sens. Paul S. Sarbanes (D-Md.) and Paul E. Tsongas (D-Mass.) as both repeatedly pressed the retired general, who served as White House chief of staff for the final 17 months of the Nixon administration, to make what Sarbanes called "value judgments" about many of the abuses of the Watergate period.

Watergate was "illegal and stupid," Haig told the Senate Foreign Relations Committee. "Mistakes were made. But I didn't make them."

"I wasn't there when they were made," he said angrily. "I inherited a situation then, and, as a consequence of those mistakes, I did my best to keep the country on an even keel."

Several times Haig told his challengers that he had "never . . . participated in an action that I consider to be illegal or immoral. I didn't then [during his time in the White House] or in 37 years of military service."

Sarbanes, however, continued to tell Haig to pretend that he never even had worked in the White House and simply tell the committee whether he thought things like wiretapping, various covert foreign policy activities at the time and other actions were "right or wrong."

"What do you want me to say? What are you after?" Haig responded, repeating that his actions were legal, but that the actions of some others were not. "There were tremendous abuses," Haig said, and they were on "both sides," an apparent reference to some who were trying to oust the embattled Nixon.

But Haig described the battle surrounding rounding the White House in those days as "honest differences among honest men. That's what governments are all about, even when the seamy aspects of government" are the subject.

"Nobody has a monopoly on virtue, even you, senator," the visibly angry Haig told Sarbanes.

Tsongas told Haig that he, Sarbanes and others among the committee's Democratic minority were troubled by a combination of factors. "Your capacity is extraordinary," Tsongas explained. "Anybody who has sat here and watched you has got to walk away impressed. But how far do you or don't you go" on these issues that have been raised?

"The more we press you the more we get into glaring back and forth across the table. Every time there is some obvious way of saying it was wrong, it will not happen again, well, we don't get that."

Tsongas told Haig he thought Haig would dominate not only the Cabinet but possibly the president. "You are going to be America, so it's very important for us to have a sense of where the limits are. We are almost beseeching you for that kind of reassurance . . . that we are not going to see the kinds of things that stained America . . . and we are not getting it, and I am very troubled by this because if we don't get it now I don't know where we'll get it," referring to the likely conclusion of the hearings in another day or two.

Haig, who has repeatedly stressed that his role in serving Nixon was carried out loyally and legally, told Tsongas that he was sorry if he hadn't offered them mea culpas, or assumption of blame, if that's what the senators wanted or needed to reassure them, but "I just can't give them, because I don't feel them, and I'd be deluding and deceiving you if I were to do so."

Whether or not the Democratic questioning got to Haig, he returned after a recess with a statement that laid out in more detail his views on what were and were not abuses of the Watergate ear.

"The break-in at the Democratic national headquarters and the [subsequent] obstruction of justice," Haig said, "were improper, illegal and immoral, an affront to the fundamental values I cherish and we all share."

Actions that he doesn't consider immoral, he said, were the secret bombing of Cambodia sanctuaries used to provide haven for Vietnamese troops who were attacking U.S. forces, and the Christmas bombing of North Vietnam in 1972, needed, he said, to conclude the peace negotiations and get back U.S. prisoners of war.

As for Nixon, Haig said, "I cannotbring myself to render moral judgments. That's not for me. It's not in me. I'll leave that to others and to history."

The United States, Haig said, perhps as some more official note of reassurance, "has a special responsibility to conduct itself with honor and generosity," and it would be "my firm intention to fulfill these responsibilities in accord with the law and the Constitution."

While Haig was out of the hearing room preparing his statement, a stinging call for rejection of his nomination came from Sen. Lowell P. Weicker Jr. (R-Conn.), a key and vocal member of the Senate committee that investigated the Watergate scandal in 1973-74.

Weicker, who is not a Foreign Relations Committee member but had asked to testify, told the panel that he was "not here with any new bombshells," but that he opposed Haig for "the record as I know it, the man as I know him."

Weicker said the phrase "weary of Watergate" was a buzzword excuse for "not performing the tough part of our job as senators," and that to let Haig's nomination pass "without demur" would be to accept the standards the nation rejected in 1974.

Weicker said the committee should be guided by how Haig observed the constitutional execution of justice rather than Nixon's definition of it. He said the secret tape recordings of White House conversations would have been the best evidence for the Watergate investigating committee. "And yet, with Gen. Haig's knowledge, the evidence was held back," though, Weicker said, it has been used selectively in an effort to exonerate some individuals, such as former Nixon aide H.R. (Bob) Haldeman, and to discredit others, such as former White House counsel John Dean.

Weicker advised the Democrats to persist in their demands to get those tapes before Haig is confirmed by the full Senate, arguing that once the Senate finishes its constitutional obligation to "advise and consent" it will lose in any court case to get the tapes.

Sen. Barry M. Goldwater (R-Ariz), who also had asked to testify, defended Haig, saying that the nation owed him its gratitude for keeping Nixon from "ruining the country" and for helping to get him to resign rather than have the country go through months of a prolonged crisis.

Weicker's sweeping indictment of Haig seemed to stun many of the committee members. Sens. Jesse A. Helms (R-N.C.) and Christopher J. Dodd (D-Conn.) asked Weicker for some evidence to back up his charges. Weicker pulled out a stack of books and said he was prepared to do so.

Haig was also defended by another outside witness, retired Republican senator and longtime committee member John Sherman Cooper. He seemed to have little impact on the panel until the close of his comments, when he looked back on his 20 years in the Senate and said that, while some things are doubtful and while perhaps there might be something questionalbe in Haig's record, there didn't seem to be anything contradicting the principles of due process of law, presumption of innocence and no guilt by association.

Despite the continuing controversy over Haig, the committee agreed late yesterday to complete his testimony today and vote on his nomination Thursday. They also waived a requirement to file a report, which means the full Senate would have time to act on Haig's confirmation on Tuesday, Inauguratin Day, with the rest of the Reagan Cabinet.

Though Haig is viewed as certain to be confirmed, sources said last night that the Republicans may opt to delay voting on Haig and the controversial Interior nominee, James G. Watt, until after the inauguration, since there could be some objection on the Senate floor. Haig is reported to be angry at the prospect of any delay beyond Jan. 20.

To complete the clashes yesterday, committee Chairman Charles H. Percy (R-Ill.) also came under fire from Democrats for pointing out several times that the Republicans have the votes to force a vote soon, in time for Haig to be installed before the inauguration. Sen. Edward Zorinski (D-Neb.) said he was offened by such threats and that they were not in the tradition of the Senate panel.