Ascents and descents.

The Spiral Staircase: My Climb Out of Darkness, by Karen Armstrong. Knopf.

"Other people seemed to progress much more smoothly through life ... but ... I kept getting derailed, ejected from one job, one lifestyle after another," writes Karen Armstrong in The Spiral Staircase: My Climb Out of Darkness. For more than a decade, Armstrong has been the author of indispensable books that have mapped the common ground between Judaism, Islam, Christianity, and, more recently, Buddhism.

Before that, however, she was a pre-Vatican II nun who left her order, a student and teacher of English literature who was refused an advanced degree by Oxford University, a television writer and personality, and a sufferer of temporal lobe epilepsy, which went undiagnosed until she was in her 30s. In her new book, Armstrong relies on the image of the spiral staircase, used by T.S. Eliot in his poem "Ash Wednesday," to describe both the repeated stripping away of her hopes and her gradual ascent to a fulfillment she had not expected.

Billed as "the story of her spiritual journey," The Spiral Staircase is memoir rather than autobiography. Armstrong provides not a linear, exhaustive account of what has happened to her but reflections on where key events and decisions have led her. She reaches back occasionally into the convent experiences she covered in her first book, Through the Narrow Gate, published more than 20 years ago, but concentrates on the circuitous route she has taken from there to her current calling--studying the sacred texts of many faiths and writing such books as A History of God: The 4,000-Year Quest of Judaism, Christianity, and Islam.

Particularly since Sept. 11, Armstrong has combined scholarship with the public advocacy of "compassionate action and practically expressed respect for the sacred value of all human beings, even our enemies," speaking widely on Islam.

THE SPIRAL STAIRCASE is not Armstrong's first attempt at a sequel to her first book. As a young woman looking for both a new vocation and an income, she was persuaded to write Beginning the World on the heels of Through the Narrow Gate, before she had enough perspective on her new, lay life. She doesn't shrink from pointing out other mistakes as well, such as her appearance in the early '80s on the "lust" installment of a live television series on the seven deadly sins, opposite a newly feminist Linda Lovelace and a drunken Oliver Reed. "The experience convinced me that I could not make a career out of being a former nun."

We see how she has weathered depression, a suicide attempt, and career setbacks that would have permanently marginalized less openhearted people--if they survived at all. With the help of Eliot's poetry, Armstrong explains her primary survival skill--to accept who she is not, and to gradually build instead on the foundation of who she is. She might be "damaged," but she is willing to grow by reaching both inward and outward, to transcend ego and find faith by emptying herself rather than by subscribing to a fixed set of beliefs. Her recurring "new joy" is "a lifelong task, requiring alert attention to the smallest detail, dedication, and unremitting effort." It is an individual pursuit: "When you follow somebody else's path, you go astray."

We are left with the picture of a small, largely solitary, but heroically determined woman--just, we suspect, what Armstrong intended, if there is ego in her self-portrait, we forgive her. By now we trust that the picture is a true one. And because Armstrong has found her own healing, we also listen with attention when she asserts that "our task now is to mend our broken world; if religion cannot do that, it is worthless."

Jo Ann Heydron, who lives in Palo Alto, California, writes fiction and poetry.