THE PRESENCE OF ABSENCE: ON PRAYERS AND AN EPIPHANY by Doris Grumbach, Beacon Press, Boston, 126 pages, paperback, $13.

God happened to Doris Grumbach in the 1940s. Sitting alone on her back porch in a village near New York City, she was visited by a “unique feeling of peace, an impression so intense that it seemed to expand into ineffable joy, a huge delight.”

The feeling lasted for only several seconds but had a profound effect on her life and is the basis, all these years later, for a probing and self-revealing discourse called “The Presence of Absence: On Prayers and an Epiphany,” published in 1998 by Beacon Press and released this summer as a $13 paperback.

Grumbach, who lives in Sargentville, has labeled her visitation as God. Now in her 80s, the writer whose works include novels, memoirs and countless articles has set out to examine that early experience in the hope of both understanding and re-inspiring it in her life.

The approach Grumbach takes to this spiritual inquiry is informed by a previous career as a scholar. In the tradition of academics, she sets out to research, to analyze, to summon. Fairly quickly, she learns that her topic is, in some profound way, unresearchable, unanalyzable, unsummonable. But she’s in good company when she heads toward a stack of books by others who have taken similar quests — Thomas Merton, Henri J.M. Nouwen, Simone Weil, Kathleen Norris, to name a few.

“The Presence of Absence” documents the findings that challenge her, confuse her and comfort her. But Grumbach is not an easily comforted thinker. Not only does she battle the pain of a chronic illness during this two-year contemplative study, she also wages war on her lifetime passion: words. It is the great irony that underscores the thoroughness of her pursuits; she must give up the very element that has reliably brought her knowledge in other aspects of her life.

“One’s own words: how tricky, even deceptive, they are, how lacking in authenticity, how far from exact,” she writes. “I wanted to reduce meditative prayer to nothing, no words, because I had begun to distrust the vehicle of words.”

Yet it is through the words in her book that Grumbach quietly joins a greater spiritual community, not the one from which she has explicitly subtracted herself by no longer participating in public worships, but a more global one that includes theologians and mystics and social philosophers.

Grumbach’s “plunge into the cold waters of silent singularity” is a search for God through self and through prayer. She no longer wants this in the form of rituals at church services or intermediaries in the pulpit. Her body aches and her mood is crotchety. Understandably, she wants to know God directly and exultantly, like that day on the porch.

In straightforward prose that has an intelligent elegance to it, Grumbach reveals the expedition of a lifetime, one that takes place inwardly and intimately. Her thoughts have touches of wit, but generally she is not in a good mood about most of this. In spite of her resistance and practicality — or perhaps because of them — she comes across with humanity and vulnerability. It seems likely that “The Presence of Absence,” which was given a readers choice award by the Boston Globe last year, is on the way to becoming a guide not only for readers of an advanced age, but for anyone engaged in or seeking a prayerful life.

In the end, Grumbach’s is not a story of any particular triumph. It is a face-off between one woman and her vanity, fear, longings and constancy. Although the “spiritual radiance” she once felt never returns, it has guided her life — at times elusively, at times insistently — to this prayerful, contemplative and devoted point.