Compelling spring reading; A woman's search for identity From Housewife to Heretic, by Sonia Johnson. New York: Anchor/Doubleday. 408 pp. $8.95.

This is the story of Sonia Johnson's discovery of feminism in 1976 and her subsequent excommunication from the Mormon Church in 1979, for her feminist beliefs and her work on behalf of the Equal Rights Amendment.

Mrs. Johnson's perception of some of today's most significant social and political issues makes this book an excellent and timely primer on the women's-rights movement. She writes candidly about what she calls the ''authoritarian, hierarchical thinking that is prevalent in many churches today, notably those that make up the New Right.'' She says it's time to stop blaming women entirely for the demise of the family and examine instead the ''irresponsible way patriarchal society teaches men to behave in human relationships.''

In this story of one woman's search for faith and identity, Mrs. Johnson describes the ''effort to know God'' as ''the most basic, most important of philosophical struggles.''