In a message to President Carter, Israeli Foreign Minister Moshe Dayan has tried to take the sting out of his publicized remarks that the U.S.-Israeli accord on Middle East peace talks was hammered out in "brutal" talks with Carter.

In the message, transmitted through the State Department on Friday, Dayan told Carter that their talks in New York on the night of Oct. 4-5 had been "decent, pleasant, useful, constructive and productive," despite the difficulty and complexity of the issues involved.

Dayan, in an interpretation likely to generate a linguistic debate of its own, told Carter that he wanted to clarify his use of the term "brutal" to describe the talks during a briefing of legislators members last week.

The Hebrew word that can be literally translated into English as "brutal," Dayan said, carries more of a connotation of "serious."

Administration officials were pleased with Dayan's explanation and saw no need to consult Hebrew scholars.

In an interview with Israel Radio yesterday, Dayan said he did not know if "brutal" was the right word to describe his talks with Carter.

"There were parts in the talks which . . . were difficult or very difficult, particularly when the President accused Israel of hampering or preventing progress toward peace more than the Arab states - let us say more than Syria.

"When I said in the Knesset (Parliament) foreign affairs and defense committee that there were difficult parts in the talks which lasted several hours, and I used the term brutal, never once did I say that we were asked to agree to something on procedural matters . . . and that because of such pressure such things were included," Dayan said according to the broadcast monitored here.

Dayan's radio interview was designed to counter harsh criticism of the Begin government's decision to approve the six-point U.S.-Israeli working paper for the reconvening of the Geneva conference.Yesterday, former Prime Minister Golda Meir charged that Israel had accepted an American "dictate" without a struggle, giving up too much in the process.

"Never, from 1967 until this (Begin) government did we accept an American dictate, although we did have arguments," she declared.

Dayan said in the interview that "there was no attempt to dictate anything to us" during the talks with Carter.

Meanwhile, President Anwar Sadat of Egypt said yesterday that he was "very, very optimistic" about Middle East peace prospects because of what he termed an "unprecedented" position taken by Carter on the Palestinian issue.

"With the advent of Carter, something really new happened. Carter said the Palestinians should have a national homeland and this is something totally new to the United States. He said all the parties must sit at Geneva. What is even more beautiful is that Carter says the Palestinian issue is the core and the crux of the whole problem. The American position has thus evolved to a point which is incredible and unprecedented."

Sadat made the remarks in talks with a group of Jordanian journalists.

In other Middle East developments, wire services reported the following :

Two bombs exploded in Jerusalem's Old City yesterday, injuring two person. Another blew up in the coastal town of Netanya without causing injuries. A group called the Arab Revolutionary Movement claimed responsibility for the latter threat.

In Beirut, political observers raised the possibility that a Palestinian physician, Waddi Haddad, coordinates terrorist activities of leftist groups in West Germany and Japan and radical Palestinian groups. Haddad is chief of foreign operations for the radical Popular Front for the Liberation of Palestine, which is headed by another physician, George Habash.