Here are five things that happened at a party at the Corcoran Gallery last night for Philip Habib, the U.S. special envoy to the Middle East:

* Israeli Prime Minister Menachem Begin sent a message to Habib, saying that the reason the PLO got out of Beirut was not because of Habib's diplomacy -- but because of the Israeli Army. But guests never heard that. Sen. Charles Percy (R-Ill.), who was reading the message, censored it. He told a few guests afterward he felt it would have been inappropriate at a party in Habib's honor.

* Charles Malik, who is something like the Middle East's Averell Harriman, read an impassioned letter from Lebanese President Amin Gemayel which said: "Greater than the tragedy of war is the torment of a sham peace. And Lebanon continues to suffer from precisely such a peace . . . We appear to have come up against an impasse . . . a way out must be found."

"You can count on us," Habib responded.

* Defense Secretary Caspar Weinberger, who was eating dinner and didn't much feel like talking about the president's decision to compromise on the MX missile, said, "I've been in two reception lines, I've given one speech, I'm tired and I'm hungry. We're discussing it. Where's my napkin? We're discussing it."

* "Goddamit!" Habib was heard saying, not angrily, to Egyptian Ambassador Ashraf Ghorbal. "You gotta give him some credit for consistency and credibility!" Although it was unclear who they were talking about, huddled as they were next to a marble column at the gallery, it sounded serious.

* The pianist of the evening, George Foca-Rodi, didn't hear his introduction and had to be fetched from backstage.

The party was the work of John Wallach, the foreign editor of Hearst Newspapers. He's known and written about Habib for years. Once, Habib came to visit Wallach's sick father in Washington. Wallach got the Hearst Corp., which owns 12 newspapers, a cable outfit, publishing houses and 22 magazines -- including Good Housekeeping and Cosmopolitan -- to pay for the evening. Some thought it was an unusual thing for a reporter to do for a source.

"There are times when the line between a reporter and the people he covers is less important than the relationship between two human beings," Wallach said. "And there's nothing I get out of it. If I asked him for an interview tommorrow, he'd say no to me -- just like he would to any other reporter."

The several hundred guests were all dressed up in tuxedos and long dresses. Lebanese Ambassador H.E. Khalil Itani and Saudi Ambassador Faisal Alhegelan came from the diplomatic corps. Richard Fairbanks and Nicholas Veliotes came from the State Department. Geoffrey Kemp came from the National Security Council. Former ambassador Ellsworth Bunker was there, as was former Mideast negotiator Sol Linowitz. Buffy Cafritz and Steve Martindale were among the socialite contingent. Attorney General William French Smith and White House Communications Director David Gergen sneaked in late.

Habib has been back in Washington to figure out what to do next in the Middle East. One senior administration official said this week that he and President Reagan talked about what tactics and pressures the U.S. could use to get things moving. But before he goes back, Habib is taking two days of vacation in Florida.

Habib seemed genuinely moved by the evening and the messages, which also came from Egyptian President Hosni Mubarak and former secretaries of state Alexander Haig and Henry Kissinger. Kissinger wrote that Habib was "Brooklyn's answer to Metternich and Bismarck, and I should know."

Habib, a Lebanese American, is the son of a grocer from the predominately Jewish Bensonhurst section of Brooklyn.

"It's a long way from Brooklyn," he said last night. "And it's a long way for someone like myself--who never dreamed he'd be walking in the hallways where I've been walking."

The evening itself was a late one. First there was a concert by Foca-Rodi, then the speeches and then, at 11, dinner. Weinberger, anticipating the worst, said he had had a peanut butter sandwich earlier.