here was a time, during the early 1950s, when Lawrence Douglas Wilder firmly believed that buildings must burn and bombs explode before blacks could find justice in Harry F. Byrd's Virginia.

"I wrote that we would never achieve our possibilities unless there was the shedding of blood," said Wilder of his days as a college student who studied in segregated libraries.

The radical sympathies were long ago abandoned by Wilder, a flamboyant, acid-tongued state senator from Richmond, who has emerged in recent years as the undisputed kingpin of black politics in Virginia.

But the fires that once fueled Wilder's rebelliousness still flicker. After a 13-year legislative career as a loyal Democrat, he recently broke ranks with his party, denounced the "magnolia mentality" of its leaders and castigated their policies for shunting aside the interests of the state's 1 million black citizens.

This weekend, Wilder, the grandson of a slave, is expected to finally decide whether to mount an independent campaign for the U.S. Senate seat of retiring Sen. Harry F. Byrd Jr. It is a candidacy that many believe would redefine the state's political dialogue, stirring up racial issues that have long been buried beneath the state's genteel conservative tradition.

"It would raise the consciousness about issues in a way that's incredible in the history of Virginia," said Henry Marsh, the black mayor of Richmond and sometime political rival of Wilder's. "I think Sen. Wilder has already raised the level of thinking about blacks in the political process. It's going to be in the dialogue for a long time, regardless of whether or not he runs."

Many Democratic leaders have warned Wilder that he would risk more than being stripped of his seniority in the state Senate by mounting an independent race for the U.S. Senate. They also have told him that his candidacy would hand Byrd's seat over to Rep. Paul S. Trible of Newport News, the expected Republican nominee, and tear apart the Democratic Party. Those are consequences that Wilder says do not bother him.

"I know this can very well be the denouement of the Democratic Party the way it is now," he says of his threatened candidacy. "But after that happens, it can always be rebuilt."

An adept political infighter who has always moved easily in the state's white power structure, Wilder's journey down the road toward his renegade candidacy has baffled and frustrated his legislative colleagues and friends. It certainly has not sprung from personal discontent. A successful trial lawyer, the 51-year-old Wilder enjoys a life style that some call lavish--he wears stylish, three-piece suits, owns two Mercedes-Benz automobiles and lives in a 15-room Georgian home in a well-to-do integrated neighborhood.

Nor can Wilder complain about his role in the new Democratic administration of Gov. Charles S. Robb. More than virtually any other senator, Wilder has been a confidant of Robb, who has regularly consulted with the legislator on black issues and given him an unprecedented role in the naming of blacks to state jobs.

"We probably call Doug Wilder's office a minimum of two or three times a day," says Robb's secretary of the commonwealth, Laurie Naismith, who is charged with filling about 1,800 patronage jobs on state boards and commissions.

"Gov. Robb has really gone the last mile in supporting the blacks," says Sen. Adelard L. Brault (D-Fairfax). "It just goes to show, you give somebody an inch and they want two miles. Wilder has been given a mile and now he wants 10 miles."

Efforts to mollify Wilder have repeatedly backfired. Last Wednesday, Al Diamonstien, state Democratic chairman, and Alson Smith, Robb's chief fund-raiser last year and the chairman of the House Democratic caucus, asked Wilder to lunch in a last-ditch effort to persuade him against running.

Wilder suggested the restaurant in the lower level of the exclusive Commonwealth Club, an all-white, male bastion of the state's conservative establishment. But when Wilder picked up his companions at the State Capitol and headed toward the club, Smith, a club member, grew skittish.

"I'm not going to take you-all in there," Smith finally said, according to Wilder and state Senate Clerk Jay T. Shropshire who was also in the car.

"You just don't want to take me in there," replied Wilder. They ate elsewhere, but the meeting might as well have never taken place.

"Wilder knew what he was doing," an angry Smith said later. "I've never seen anybody take blacks as guests in the lower level . That's what the rules are. Look, I've done everything I know how to help blacks in this state. But he's setting the blacks back years. He's picking on something else every day, just to polarize people between black and white."

"Can't you see the irony of it?" Wilder asked. "Here we are in 1982 and he doesn't think enough of me to take me into his club. I was really hurt. It showed me, more clearly than ever, the need to do this thing."

Wilder's claim to wounded pride contrasts to a remarkably successful political career that has seen him move through the ranks of the General Assembly to become one of its most influential members. As the first black in the state Senate since Reconstruction, Wilder arrived in 1971 and immediately alienated the old guard by introducing a bill to repeal the state song, "Carry Me Back to Old Virginny," with its lyrical references to "darkies."

Today, though, Wilder is himself a fixture in the Senate hierarchy. He stands eighth in seniority in the 40-member body and chairs two committees, transportation and the powerful Democratic steering panel, which divvies up committee assignments for the rest of the Senate.

"He's one of the most astute politicians I have ever seen," says Sen. Wiley F. Mitchell (R-Alexandria). "He knows how to use the level of powers in the Senate as well as any other man there."

The classic example of that shrewdness came two years ago when Wilder maneuvered a bill to create a state holiday honoring Martin Luther King through the Senate by attaching King's name to Lee-Jackson Day, the holiday honoring Virginia's two most venerated Confederate heroes.

By the time the bill made it to the House, the Daughters of the Confederacy and like-minded groups were up in arms. "The Lee-Jackson people came out of the ground," recalled Wilder, as he cackled with laughter. "They said, 'Any other day, any other day, not our day.' "

Wilder, with a great flourish, strode into a House committee room and immediately offered to oblige. He suggested that King be honored on the slain civil rights leader's Jan. 15 birthday, which, of course, was the date Wilder wanted all along. In that form, the bill finally passed the legislature, but was vetoed by former Gov. John N. Dalton, a Republican.

Wilder's legislative acumen is supplemented by a booming voice and biting wit that have made him what Senate Clerk Shropshire calls "one of the two or three best orators" in the chamber. "He probably makes the most effective use of sarcasm of anybody I've ever seen," adds Mitchell.

The wit has been on ample display in recent days as Wilder has conducted his guerrilla warfare against the Democratic Party. On Tuesday, Del. Owen B. Pickett--the obscure state legislator originally annointed by Robb and other party leaders as their U.S. Senate candidate--released his delegates to the state party nominating convention in an obvious attempt to coax Wilder back into the party.

But Wilder blasted Pickett's move as a "total, empty gesture" because, he said, the Virginia Beach legislator had already stacked the convention with more than enough supporters to guarantee him the nomination. "Even Ray Charles could see through this one," said Wilder, in a typically blunt assessment.

Wilder's stature may have grown larger under the new Democratic administration, raising the expectations that many blacks in Virginia have from both the state government and the Democratic Party. Wilder himself has found his relationship with Robb has opened him to attack from some blacks.

In a letter to a black political group that got prominent play in the Richmond Afro-American a few months ago, Wilder was accused of "political treason" for having "sold out the black community as a result of his incestuous relationship with Governor Robb."

The critic was an old and bitter personal opponent--Sa'ad el-Amin, a local black activist-lawyer and radio talk show host who represented Wilder's wife in his divorce a few years ago. El-Amin charges that Wilder only began talking about a U.S. Senate race in order to grab publicity and shore up his support among local blacks.

"The man is an egomaniac," el-Amin said. "He isn't committed to anything except Doug Wilder . . . . I pressured him and that put a lot of heat on Wilder within the black community."

For his part, Wilder refuses to respond to anything el-Amin says. "He does not exist," says Wilder.

Whatever the motivation, Wilder first began attacking the Democratic leadership in March after the el-Amin letter and after two of his bills--one for a Martin Luther King holiday and another banning state tax exemptions on segregated schools--were killed in House committees. At first, he attacked House Speaker A.L. Philpott (D-Henry) for stacking key committees with legislators hostile to black interests.

Of Philpott, the conservative Southside lawmaker who recently referred to black delegates as "boys," Wilder is openly bitter. "I am prepared to do whatever is necessary to change the situation with reference to the Philpotts being where they are," he says.

From these attacks, it was only one small step to a wholesale indictment of the Virginia Democratic Party (Robb excepted)--its dismal record on black judgeships, its sponsorship of a succession of discriminatory redistricting plans, its support for Pickett, who had began his campaign by invoking the name of Sen. Byrd.

Relaxing in his Richmond law office cluttered with freshly minted campaign buttons, Federal Elections Commission forms and other accessories of his impending candidacy, Wilder sought to explain his recent course by recounting the legacy of his childhood in a segregated society.

His grandfather, James Wilder, was a Richmond slave whose wife and children were sold to another family near Ashland, 25 miles to the north, shortly before the Civil War.

"My father used to tell me about the whippings his father used to get for going off to see them," he recalls. "It left a searing impression on him. But he was too proud to talk about it that much. The thing he spoke more about was the Byrd machine and how much Byrd was against poor people and black people."

As a youth, Wilder attended segregated public schools and worked his way through Virginia Union University washing windows and waiting tables at downtown Richmond hotels. He graduated as a chemistry major, but when he returned from the Korean War with a Bronze Star and applied for a position with the state Health Department, "the only job they had for me was as a cook at the Hanover School for Boys."

Wilder's dream was to be a lawyer, but no blacks were permitted in Virginia law schools at the time. The state did, however, offer $300 stipends to black youths to attend law school out of state, which Wilder did at Howard University in the District of Columbia. The stipend was "to get rid of you, to keep you out," he says. "That was in 1956. We're not talking about 100 years ago."

As a lawyer and legislator, Wilder says he has frequently suppressed his resentments and paid homage to the state's genteel tradition. "You don't deal in excess, you don't say anymore than is necessary," he says. It is a tradition he says his Democratic friends have urged him to continue, darkly threatening reprisals, such as stripping him of his committee chairmanships, if he pursues his plans to run.

"If I wanted to be comfortable, all I'd have to do is be quiet and let things go," says Wilder. "But I could never live with myself if I didn't speak up and make challenges from time to time."