The Adas Israel Men's Club drew an unusually large crowd yesterday morning - and just as many women as men - despite the substitution of Danish pastry for the usual three-course brunch.

The reason was the presence of a bonafide Egyptian in their midst. Mohammed Hakki, minister-counselor for press and information was coming to the Adas Israel Congregation, at Connecticut and Porter Streets NW, to talk peace, even as the Israeli and Egyptian governments seemed to be having second thoughts on the subject.

"When we think of Egypt, it recalls our common roots," said Rabbi Stanley Rabinowitz in his introduction. "There is no greater rivalry than sibling rivalry."

Hakki's appearance had been arranged well in advance, and the unspoken concern of his audience was that last week's developments - the suspension of negotiations - might have a chilling effect on the morning's proceedings.

When the proceedings were over, however, had the parties been asked to issue a joint communique, they might well have used the word "cordial" to describe the atmosphere.

The Egyptian had recalled a number of what he saw as Israeli-inflicted injustices, but he had done so without compromising the basically upbeat tone of his remarks. "Is this the end of the romance?" he asked. "Or are we at the threshhold of the romance? My answer is unqualifiedly yes."

His Jewish hosts, while finding opportunities to cover virtually all the bases of the official Israeli negotiating position, welcomed and later thanked Hakki profusely.

"Why did President Sadat withdraw his negotiators when they had already agreed on five of seven points?" asked one member of the throng.

"That is the brilliance of Mr. Begin," said Hakki. "His points six and seven are what's most important. The rest is just embroidery."

"Do you expect Israel to accept a divided Jerusalem with removal of rights to visit sacred places?" asked another.

"Nobody is asking for denial of rights to visit sacred places," said Hakki. " . . . I don't think any Arab will accept Jerusalem to become the capital of Israel."

In the course of another response, Hakki declared that "we have never harbored any ill-feelings toward the Israeli or the Jewish people." At this, a gray-haired woman in the third row whispered to a neighbor. "How can he say that?"

Another questioner asked why Egypt was resisting the idea of demilitarizing the Sinai. "We can devise any number of schemes or stages to prove that we can live in peace," replied Hakki, "but if I say to you, find. I leave your living room, but I leave behind a soldier and an airport . . . this is unacceptable."

When the questioning was over, Aaron Paulson, a member-in-good-standing of the Adas Israel Men's Club, summed up his impression of Hakki - "a good diplomat . . . he glosses over things."

Up on the podium, meanwhile, Rabbi Rabinowitz was saying that it would be inappropriate for him to use the occasion "to debate or to score points." Barely a minute later, he was responding to Hakki's argument on the Jerusalem question. "Are Jews to be regarded as less trustworthy guardians of rights than the Christians or Moslems?" he asked. As for the Sinai, "the real issue," he said, "is not settlements but militarization." How could Israel be sure the Sinai would not be used as a "staging area?"

Donald Wolpe, a past president of the Adas Israel congregation, praised Hakki for coming, and then found time to recount some recent Mideast history, amending and correcting Hakki's analysis as he went along.

"We want Palestinians to be free," said Wolpe, but he described the dislocations that had occurred since 1948 as a fair "population exchange" between Israel and its Arab neighbors.

"I want to thank you for the kind words," said Hakki, when he was given a chance to respond. "And I would like to go back for a moment to 1967 . . ."