WHEN JOHN GERNAND came back to the Phillips Collection for a visit the other day, the whole place turned out. Women came up and kissed him. Director Laughlin Phillips shook his hand. The two-person elevator that he favors because of his arthritis was waiting to take him to the top-floor library, where the staff had put up several of his paintings. His cup of coffee was ready, with half-and-half, even. The gallery cats, Fiona and Bazooka, writhed around his ankles and got up in his chair and tried not to seem to be staring at the half-and-half.

You would think he was Robinson Crusoe coming home. In fact, Gernand retired just last month at 69 after 44 years at the Phillips. He had been its registrar and archivist for 10 years, but it goes back a lot further than that.

"I never had any museum training," he said. "I studied painting at the Phillips art school in Studio House, up the street. Marjorie Phillips gave me a scholarship there for four years. Then I worked here half-days, and when World War II started I came on full time."

There is a photo of a wavy-haired young Gernand in suit and tie at his easel in what is now the library. It is a class with a live model (clothed), and his place is at the French window under the big skylight. Before that, the room was Laughlin Phillips' nursery. It's that kind of museum.

"You never forgot it was their home. They would almost always bring a picture here before buying it, to see if it fit in. And sometimes it didn't, so they sent it back even though they liked it. Duncan Phillips never bought anything because it was in fashion or it was on the market. For one thing, the collection wasn't all inclusive, and the money wasn't unlimited. And then, they bought things for sheer love."

One painting the Phillipses bought the instant they saw it in New York was Degas' "Dancers at the Barre." When Gernand showed the great watercolorist John Marin through the place they spent some time in front of it, studying the dynamics, so important in Marin's work.

Marin, by the way, had nice things to say about Gernand's own subdued, lyrical paintings.

Many a famous visitor has made the tour in the quietly charming company of John Gernand: Dylan Thomas ("on his best behavior; didn't care much for pictures; asked me out for a drink"), Yehudi Menuhin ("When he saw Bonnard's 'Open Window' with those violet and orange stripes and spaces, he said, 'I think I could play that on my violin.' He was very responsive"), Willem de Kooning ("very Catholic tastes").

Many others passed through without announcing themselves: Gallery policy is to leave people alone. He remembers Noel Coward, Ingrid Bergman, Katharine Hepburn, Rex Harrison and Lilli Palmer . . .

"Harrison saw a de Stae l we had just got for about $3,000 and said, 'Oh! We almost bought that! Well, it shows I have good taste.' It's worth a fortune now, of course."

Back in the early days when the collection was taking shape, when Gernand and the late James McLaughlin and a few others were the whole Phillips staff, he helped unpack the new works.

"I remember when the Matisse 'Studio' came in and we took it out of its crate. So exciting!"

One of the best times was when Marjorie Phillips single-handedly put together a major Ce'zanne show in 1971, summoning up pictures from the Louvre and any number of American museums and even luring "The Black Clock" from Stavros Niarchos. The place was packed. Lines halfway around the block. Special Pinkerton guards. Extra student guards. Then, as now, the Phillips always tried to hire young artists.

"Everybody in Washington came here sooner or later. It was a word of mouth gallery for years. The concerts began in '41, and that helped. Sometimes there would be just 12 visitors in a day. And a lot of them didn't know art the way the public knows it now. We hadn't had all those Time and Life art reproductions. People would make fun of Klee and Picasso. One lady rushed out complaining that Klee was obscene."

He says Duncan and Marjorie Phillips treated their people as family, and you do sense that somehow the Phillips house was his own childhood home. All those rooms, the reception rooms, the music room, the little bedrooms with their fireplaces, the corridors and staircases: They are part of his life landscape. The little Gauguin was here, those Bonnards were there, the Corots and Daumiers and Monets and Renoirs in their places.

He talked of his farewell party, when he sat in a Louis XV chair between a van Gogh and a Ce'zanne, with an ivy wreath on his head, and people read poems to him and gave him a Waterford bowl and an electric typewriter.

He had finished his coffee now. Women were still coming into the room to kiss him. "I might write a mystery," he mused. "I read 'em by the hundreds. I may do a new guidebook for the Phillips. And I'll resume my painting. But for now, I'm just enjoying not getting up with the alarm clock."

About the picture for the newspaper: Would he like it done in his own apartment?

"Well," he said diffidently, ". . . or we could do it here."