When Virginia blacks gathered here for their annual state NAACP convention, there was some initial talk that the Rev. Ralph Abernathy might be asked to drop by and explain his surprise endorsement of Ronald Reagan.

But the idea, broached at the group's board of directors meeting Friday night, was quickly abandoned -- even though the prominent black leader is attending a religious revival in neighboring Norfolk.

"The suggestion was mentioned and coolly received," Jack Gravely, executive director of the 25,000-member organization, said today.

Another NAACP official, putting it more bluntly, said the notion of inviting Abernathy "was hooted down."

This resort city's Pavilion Hall was clearly Carter country, and most of the 3,000 delegates attending the state convention, the NAACP's 45th, this weekend wanted to keep it that way. Few bothered to hide their anger over Abernathy's sudden jump into the Republican camp.

"I feel the same way about the abernathy endorsement that Ronald Reagan feels," said Del. Robert Scott, a Newport News Democrat who is one of only a handful of blacks in the Virginia General Assembly.

"Reagan said he was surprised and hadn't expected it. Well, if I had his horrible civil rights record, I would have been surprised and not expected it either," Scott said.

Abernathy, the former director of the Southern Christian Leadership Conference who rose to prominenced because of his close association with the Rev. Dr. Martin Luther King Jr., announced his support of Reagan Thursday at an appearance in Detroit with the GOP presidential nominee. Abernathy accused President Carter of having "failed us miserably as black people," and said Democrats have to stop taking the black vote for granted.

But Virginia blacks attending the convention said Abernathy's endorsement would have little impact on the black vot, either in the state or nationally. Some suggested that his backing of Reagan was motivated by "personal animosity" toward other black leaders.

"This will probably encourage a number of blacks to go to the polls and make sure they vote for Jimmy Carter," predicted Virtual Murell, who is directing the minority voter drive for the Carter-Mondale campaign.

Blacks represent about 20 percent of the registered voting population in the state, and Murell said that a large turnout by them on Nov. 4 could hand Carter the Virginia victory that narrowly eluded him four years ago.

"The black vote is so critical because the black vote is so loyal in this state," Murell said. "Black Americans trust Carter. He has done a lot more for us than the Republicans have ever done or than Reagan did when he was governor of California."

Gravely, while stressing that the NAACP nonpartisan, said he expected that blacks would again follow tradition and throw their support to Democratic candidates, including the incumbent president.

The three-day NAACP convention which attracted the largest number of state delegates ever, featured workshop sessions on voter registration, unemployment and education. In addition, both Virginia Lt. Gov. Charles S. Robb and Attorney General J. Marshall Coleman -- the expected rivals in next year's gubernatorial contest -- appeared to address to the gathering.

But it was this year's election, not next year's, that dominated the convention.And although John Anderson's campaign literatures was distributed to the delegates, a lonely Reagan-Bush sign was the only visible evidence of Republican lobbying.

Not every black delegate at the convention expressed enthusiasm for the Carter administration, and a few expressed the same kind of apathetic feeling about the election that seems to be affecting a large number of undecided voters. Still, no one seemed to be seriously considering voting for Reagan.