Sen. Barry Goldwater (R-Ariz.), the conscience of the nation's conservative movement for a generation, yesterday announced that he will oppose the social legislation agenda of a newer brand of conservatives because he thinks they are trying to limit the authority of the courts.

The 1964 Republican presidential nominee said he will vote and speak against New Right senators on the school busing, school prayer and abortion measures that are expected to come to the Senate floor in the near future.

The proposals, Goldwater said in a rare floor speech, violate the constitutional doctrine of separation of powers.

A short time later, the Senate voted 63 to 33 to end a renewed filibuster against a bill that would severely restrict the authority of federal judges to use busing as a means to end school desegregation.

Although he had voted with conservatives on earlier votes on the issue, Goldwater sided with liberal Democrats and moderate Republicans this time.

The senior senator, who is 73, said in an interview that he is adamantly opposed to busing, "but I think it is dangerous for the country to limit the actions of the courts. If we limit what courts can do with busing, how long is it until we tell the courts they can't act on drunk driving or murder?"

Goldwater's remarks were significant for their symbolic meaning and the way they point out how the interests and agenda of conservatives have changed during recent years.

Goldwater said he doesn't think Congress should try to "get involved in social or moral matters" because "anytime you pass a law Americans will find a way to get around it."

"I used to make beer for my dad during Prohibition," Goldwater added. "My God, that was wrong, but people did it. Look what Prohibition did. It created the biggest bunch of alcoholics this country has ever seen."

Goldwater's statements had little, if any, practical effect yesterday. By passing a cloture motion, the Senate agreed to curb a filibuster by a small bipartisian group against anti-busing legislation. It set the clock running on a final 100 hours of debate.

The filibuster has been running off and on for 32 weeks, and liberals, led by Sen. Lowell P. Weicker Jr. (R-Conn.), yesterday vowed to continue the effort despite the vote.

Sen. Bob Packwood (R-Ore.) conceded that the effort probably will fail, eventually. But, he added, "We will go several nights all night before it's over. It will heighten awareness of the issue."

A final showdown on the busing battle, however, likely will be delayed until after the Senate returns from the Lincoln Day recess, which ends Feb. 22.

The Senate adopted the busing ban last week as a rider to the $2.4 billion Justice Department authorization bill after killing a filibuster against the amendment on the fourth try. The new filibuster was against the authorization bill as a whole.

The measure, the most strident anti-busing one ever adopted by either House, virtually would eliminate busing as a means of integrating schools. It would prohibit judges from ordering desegregation plans where students would be bused more than five miles, or 15 minutes, from their homes.

The House has passed a milder version of the same rider, but if the bill goes to conference the chief House negotiator would be Rep. Peter W. Rodino Jr. (D-N.J.), who could delay the measure.