A Virginia legislative panel, joined by dozens of banking lobbyists in a chaotic free-for-all filled with personal insults, today quickly rejected a measure requiring state banks to provide an interest-free period for any of their credit card users.

Then, as the group agreed to a compromise -- directing bankers to warn the customers of the charges they face -- state Del. George P. Beard Jr., a Culpeper Republican and a banker, suggested how the notice should begin:

"We're putting the Star of David at the top," said Beard, a member of a House-Senate conference committee debating legislation sought by Del. Bernard S. Cohen (D-Alexandria).

Beard, who made the remark twice during the panel's meeting, later said it was a joke because "that's Bernie's religion." Beard declined to explain it further and Cohen, who is Jewish, declined to comment except to say he believed Beard was trying to be friendly.

Several persons, including banking lobbyists, grimaced when Beard, the president and chairman of Second Bank of Culpeper, spoke. Last year he encountered criticism after he referred to the "five ringless fingers" of Mary Sue Terry, then the Democratic candidate for state attorney general. Terry is not married.

At the January inauguration of Terry and fellow Democrats Gov. Gerald L. Baliles and Lt. Gov. L. Douglas Wilder -- the first black elected statewide in Virginia -- Beard was overheard saying that he had never seen as many "minks, Mercedes and minorities."

State Sen. Richard L. Saslaw (D-Fairfax), who exchanged heated words with Beard during today's meeting, said later that "I'm not surprised [Beard] said it." Saslaw, who is Jewish, told a reporter that Beard "can kiss my butt."

During the conference, Saslaw, who wanted the warning printed on each credit card bill, denounced both the lobbyists and the lawmakers for agreeing to the warning provision.

It was considerably weaker than the provison that the House had approved earlier in the session. The House, in a vote that caught the banking lobbyists by surprise, voted overwhelmingly to require state-chartered banks to provide interest-free periods for any credit card purchase.

A few days later, after intense lobbying by bankers, the Senate rejected the provision and sent the issue to the six-member House-Senate conference committee. Beard was one of three members of that committee who have ties to the industry.

"That was the most shameless group of characters I've ever seen in one room," Saslaw declared after the conference met today.

"Coming from him, that's probably a real compliment," countered Jack Edmonds, a lobbyist for the Virginia Banking Association, which put on a full-court press to prevent any revival of Cohen's measure.

"Is anyone here from the consumer side?" wondered Sen. Johnny S. Joannou (D-Portsmouth), chairman of the conferees, as he looked around the crowded room.

"We are," said Edmonds, the banking lobbyist.

Only two persons -- one representing the American Association of Retired Persons and the other speaking for himself -- spoke up for Cohen's original proposal.

"There's got to be a great deal of ignorance," said the Rev. David L. Bailey, who noted the confusion even the bankers and lobbyists had in explaining credit card interest rates to each other.

The issue stems from a complaint Cohen made earlier in the session that users of the banks' credit cards are not aware that they forfeit a 25-day grace period to pay credit card bills without finance charges if they do not pay the previous month's balance in full.

Of the 2 million credit cards issued in Virginia, about two-thirds routinely have carry-over balances, according to the banking industry. Banking lobbyists said that if Cohen's original bill were enacted it would cost state banks about $30 million a year in interest.

"I caved," Cohen said, explaining why he agreed to the warning, which will take effect in April 1987. "I know how to calculate interest rates and I can count votes."

The banking forces included Morton Boyd, president of a Louisville bank that has its credit card operation based in Virginia. Boyd said his firm would lose $1 million in business if Cohen's bill passed.

"We're not going to take a $1 million hit," said Boyd, who along with other bankers intimated that he would move his operation to another state.

The panel, whose action is expected to be approved by both the Senate and the House, voted to urge the appointment of Cohen and Joannou to a planned legislative commission of banking practices and interest rates that is to report its findings in November. The panel also approved Joannou's bill to require that state banks credit payments to accounts within two days rather than the five allowed now.