IN 1979, Dr. Sukie Miller, a New Yorker vacationing in the Bahamas, bought a painting hanging in a Nassau art gallery. The artist (who signed his cardboard canvas ''Paint by Mr. Amos Ferguson'') was unknown to Dr. Miller. In fact, he was unknown to everyone she questioned when she tried, for the next five years, to track him down.
''I had given up on finding him alive,'' Dr. Miller recounts. ''But I wondered if he might be lying in an obscure Nassau grave somewhere.''
Last August, again on vacation in the Bahamas, she hired a cab to go on a cemetery check, and she gave Mr. Ferguson's name to the cabdriver. The cabbie didn't seem to need further instructions.
Driving Dr. Miller into the poor ''Over the Hill'' section of Nassau, five minutes from her hotel, he stopped before a tiny frame house sunk behind a jungle of coconut and banana trees.
''This is where Amos Ferguson lives,'' said the driver, ''Dutch'' Dean. ''I'm his best friend.'' In retrospect, he certainly was.
Since that fortunate cab ride, events have moved with uncommon grace and swiftness for Mr. Ferguson, a house painter who climbed down from his ladder into an artist's career about 15 years ago.
Introducing herself to him, Dr. Miller asked the artist if he had any other paintings she might examine. He certainly did. There were hundreds, painted on cardboard with ''Pliolux'' exterior house paint, stacked beneath his bed.
Buying two more paintings, she flew back to New York and invited a Haitian art connoisseur, Ute Stebich, to examine her purchases. Ms. Stebich, who wrote the catalog for the Brooklyn Museum's Haitian art collection, was stunned.
Together, the two women flew back to Nassau, where Ms. Stebich took slide photographs of more paintings and forwarded them to the prestigious Wadsworth Atheneum Museum in Hartford, Conn., to be considered for their African diaspora collection.
''Frankly,'' says Gregory Hedberg, the Wadsworth's curator, ''I expected to glance at the slides and send a short, polite note back to Ute (Stebich) telling her we weren't interested.'' Then Mr. Hedberg looked at the slides and radically reversed himself.
''It was just extraordinary to find an unknown artist of this quality who has been quietly working away with such purity all these years,'' he says.
In March of next year, the Wadsworth is giving Mr. Ferguson a large one-man show. In New York, the Studio Museum of Harlem has reserved its own showing date. Sotheby Parke Bernet would like to auction him as part of a large offering. And on April 4, a large group of American curators, critics, connoisseurs, and journalists attended the first Amos Ferguson Art Show at the posh Ocean Club on Paradise Island.
Paradise Island is Nassau's ''pleasure dome.'' The island, a large, meticulously groomed complex of hotels, casinos, and beaches, is connected to the rest of Nassau by a toll bridge that spans the harbor. Before Dr. Miller unearthed him, Amos Ferguson used to hang his paintings by clothespins and try to sell them among the fruit and conch-shell stalls beneath the bridge.
A tiny, mahogany-skinned man who still takes an occasional house-painting job (''if the job is important enough''), the artist seemed less overwhelmed by the fringe benefits of his success than the source of it. Wearing a pin-striped blue suit, he blinked into the klieg lights before the microphone and said succinctly , ''It's the Lord who holds me up, like He holds you up in an airplane, unless He wants to bring you down.''
His speech mirrors his paintings, which are joyful, gently indelible creations full of bright sky, birds, hibiscus flowers, and marching bands - whatever comes to him in his fertile imagination. ''I paints not by sight, but by faith,'' he explains. ''Faith gives you sight.''
Yet it was not until Mr. Ferguson's nephew, George, came to him with a dream that the artist took his avocation of painting scenes on flattened-out shoe boxes seriously.
He recalls: ''I was painting for a rich man, E. P. Taylor of Lyford Key, when my nephew came to me and said, 'Uncle Amos, I dreamed that the Lord came out of the sea with a painting in his hands, and He say He give you a talent but you don't use it.' And I said, 'OK, George, that must be the Lord.' ''
That evening, he went home and painted one of his ''sacred pictures,'' of Adam and Eve. ''I read the Bible and I start getting an understanding of things.'' Curators who have examined his work think that his ''understanding of things'' is brilliant.
''He is an outstanding colorist,'' says Ms. Stebich, ''and he is a genius at taking complex shapes and simplifying.''
''I think he has a lot to say to the young artists in New York and Paris who are trying to unload some of the heavier traditions,'' says Mr. Hedberg. ''Today's art puts an awful burden on the viewer. You just kind of want to flee.''
Mr. Ferguson himself is less analytical. ''Some people don't know what art means. They call it play toy. They don't know nothing about this line of work. But I just stay right here in the Bahamas and do what I do. I paint the same thing, but it comes different each time.''
He and his wife, Bea, live in a tiny, sofa-stuffed house full of quilts, candles, plants, and paper roses. There are two Bibles, well thumbed, in evidence. On church nights, the sofas are filled with fellow parishioners from a local Baptist church.
While Bea Ferguson pours tea, Amos Ferguson sits at his kitchen table where he paints and tells Scripture stories. He often claps his hands with enthusiasm after a particular twist of sacred plot (''That's Jesus for you!'') or grabs somebody else's hand to press it to his cheek if something said delights him. Two things irritate him: his wife's dogs and negative people. ''If somebody hit that porch and walk heavy, like they don't care, that cross my spirit and I can't paint. I know who they are before they even out of the car.''
Outside, the pie-shaped yard is a disorganized palette of color -- sea grape, sopadillie, and Jamaica apple trees, ''match-me-if-you-can'' and hibiscus flowers. All of it finds its way through the artist's brush.
He is asked what he thinks God wants people to see in his paintings. Mr. Ferguson is quick to answer. ''He just trying to let people know that He's God. He's trying to let people know to live by what He gives them, like what He give me.''