Every now and then there comes along a theater work whose integrity, depth of humanity, and artistic dimensions mark it as something beyond and above the ordinary experiences of playgoing. Though essentially tragic, it lifts the spirit and stirs the heart. Such a work is ''Poppie Nongena,'' at St. Clement's on West 46th Street. This story of a simple South African black woman's courage and capacity to survive achieves a cherished goal of art. In its uniqueness, it touches the universal.
Working from Elsa Joubert's best-selling novel, Sandra Kotze and Miss Joubert have created a drama about Poppie Nongena. The name is invented but the events it dramatizes are those of a black woman living in South Africa today. According to a program note by Miss Joubert, they were related to the author by Poppie herself and by members of her family or clan, ''and they cover one family's experiences over the past 40 years.'' The narrative unfolds in fragments. The fragments form a pattern.
The strength of ''Poppie Nongena'' as drama is that it sets out to tell a personal story rather than deliver an indictment of South Africa's racist policies. The indictment becomes implicit as Poppie's ordeal unfolds. The play begins on a happy domestic note as little Poppie (Thuli Dumakude) and her three brothers play games and sing songs under the watchful eye of Poppie's grandmother (Sophie Mgcina). Miss Mgcina, who also plays Poppie's mother, makes an outstanding contribution as actress-composer-vocalist to a production that frequently relies on superb unaccompanied singing by all the members of an excellent cast.
''Poppie Nongena'' moves from its heroine's early years, her courtship and marriage while still very young, to the struggles to maintain her growing family under the severe handicaps inflicted by South Africa's apartheid policies. Separated for long periods from her ailing husband (Selaelo Maredi), Poppie finds domestic work as a live-in maid and, after interminable delays and many applications, suddenly receives the pass that legalizes her Capetown residency. In 1971, however, she is forced to leave Capetown.
The drama's second theme emerges when Poppie's younger brother (Fana Kekana) becomes a ringleader of protest demonstrations, in the course of which he shoots a white policeman. The young blacks, it develops, are not merely defying the authorities but have become impatient with the resignation of their elders.
Near the end of the play, Poppie laments, ''My little sheep, my lambs, my poor lost sheep. What have I done wrong? Where have I sinned? . . . I have found my way through everything, but through this I can find no way. . . . But God is my witness. I never sought out this trouble. From the beginning it was not I who sought the trouble. . . .''
Miss Dumakude's extraordinary performance of Poppie embodies the patience, fortitude, unassuming dignity, and devoutness of a woman who matures as she grows. The actress's gradual transformation from young girlhood to grandmotherhood is one of the most impressive aspects of this remarkable portrayal.
The production staged by Hilary Blecher is also enormously aided by the authentic contributions of the emigre South Africans in the cast and their handling of the play's lilting language. They include Seth Sibanda and Tsepo Mokone. Maggie Soboil and Alex Wipf effectively impersonate the various white South Africans whom Poppie encounters.
As director, Miss Blecher takes full advantage of the spacious St. Clement's open stage, with its suggestions of corrugated metal shacks and floor surface embedded with pages from old newspapers. The exceptional production was designed by Jon Ringbom (sets), William Armstrong (lighting), and Shura Cohen (costumes).