''I tried retirement once some years ago,'' muses New York artist Lilian MacKendrick, ''and thought I'd give up painting and just amuse myself. But it didn't last long. By the end of three days I had discovered that there was nothing one-tenth as interesting as what I was doing. So I picked up my brushes and sat back down at my easel. Now I know that I could never live long enough to paint all the paintings that I would like to do.''
The lovely white-haired artist speaks as she sits at that same easel, in the same window, in the same room on Central Park South that has served as her studio since 1940. The walls around her are covered with her landscapes, interiors, still lifes, and portraits in oil, watercolor, pastel, chalk, and ink. Their vibrant colors suffuse the room with a glow and a cheerfulness.
She characterizes her work, in which all objects are clearly recognizable, as ''naturalistic.'' It has never bordered on abstract expressionism, the academic, or the surrealistic, nor has it been laden with social messages.
Because it has held to a middle course of expressive representation, there have been years when Miss MacKendrick was ''out of fashion.'' Now, with the new swing to realism, she is ''in fashion.'' Not that it matters much to her. She has always, since her first show in 1947, followed her own bent and held to her own inspiration, knowing she would find her own audience.
A native of Brooklyn, N.Y., Miss MacKendrick calls herself a ''born artist.'' She grew up in a large family that was involved with all the arts, and as a child she thought that everyone painted. An uncle, Louis Keila, a well-known sculptor and teacher of art, allowed his young nieces and nephews to play in his studio. ''He helped me see, feel, and think like an artist, and he also exposed me to all the great collections in New York City's museums,'' Miss MacKendrick recalls.
She also remembers the public-school art teacher who leaned down one day and whispered, ''My dear, you are an artist!'' She wasn't quite sure why, except the other children had submitted tight, clean pages with tiny charcoal drawings in the middle of them, while her pages were covered with bold, expressive drawings.
She was taught to have moral courage, she says, and trained to be an independent thinker who could provide and care for herself. That is one reason she is so pleased that for over a quarter of a century she has been able to pay her bills by the sale of her paintings, without teaching or resort to commercial work.
Miss MacKendrick graduated in 1928 from New York University with a degree in the history of fine arts, and later studied lithography at the Art Students League. During the depression years she could give little time or thought to painting. But, she says, ''After World War II, when I could get to France and study and observe, I began to paint the scenes, the flowers, the people, with fresh verve and inspiration.''
She speaks modestly about her accomplishments, although her work is now represented in over 600 private collections in many countries. She has had over 30 one-woman shows from New York; Phoenix, Arizona; and Palm Beach, Florida, to London; Paris; and Ostend, Belgium. Her paintings are in the permanent collections of numerous museums, including the Metropolitan Museum of Art in New York, the Hirshhorn Museum of Art in Washington, the Walker Art Center in Minneapolis, and the Wadsworth Atheneum in Hartford, Conn. She is listed in several different volumes of Who's Who.
She is now preparing for her next one-woman show, to be held at the Windjammer Gallery in Bermuda, beginning the last week in June. She was represented by Hirschl and Adler Galleries in New York for 11 years, and the Wally Findlay Galleries presented a 35-year-retrospective show of her work in 1981.
How does she keep the paintings coming? ''I am an optimist,'' she says. ''I have serenity. I paint serenity. And I believe passionately that life is worth living. In many ways I have gotten stronger as I have gone along. My energy has sustained my imagination and inventiveness. I feel my resourcefulness has diminished but little over the years. And although the world tells me there is little to be cheerful about, I remain cheerful. Perhaps it has something to do with my constitution.''
When a visitor notes that her studio window faces south, she comments, ''I have a feeling it is a useful thing to have the southern exposure. The light changes all day long, and I paint the changing light into my still lifes. I think it may give them more vitality.'' There is a distinct lilt about Miss MacKendrick. It comes through the ambiance she has created around her, through her conversation, and through the laughter that comes easily and often as she talks.
She has been most influenced, she says, by ancient Oriental civilizations, particularly those of China, Japan, and India. ''Connoisseur'' magazine once said of her work, ''Lilian MacKendrick has managed to fuse the most enduring principles of both Western and Eastern art.''
Has her art changed significantly? ''Yes, I have changed as I went along, because I was raised by a very strict code which dictated that once you resolved one set of problems you had to set yourself another set to overcome. So all my career I have kept setting new goals and sets of problems to overcome. So, of course, my work has evolved, and I believe the changes have brought more weight and strength to it.''
She says she dislikes the term ''self-expression,'' since everyone is expressing himself all day long. One's job as a painter, in her view, is not just to express self, but to make the best painting that talent and inspiration will allow.
Her career, Miss MacKendrick says, has given her many satisfactions, the uppermost of which is the sharing of ''beauty and pleasure and happiness'' through her paintings. That, she says, ''gives me the feeling of great service.''