It's been a quarter-century since the publication of Annie Dillard's Pulitzer Prize-winning Pilgrim at Tinker Creek, a memoir that followed her eager exploration of the natural world over the course of four seasons. Always on the lookout for signs of the divine presence, Dillard's quest in Pilgrim focused on the commonplace occurrences of nature: the insects in the creek, birds on the wing, the cedar tree in her back yard. Combining poetic language with acute, perceptive observations, Pilgrim at Tinker Creek established the Hollins College graduate as one of our finest writers, a naturalist in the vein of Muir and Thoreau with a refreshingly original theological bent.

After a career that has included poetry, a novel, essays and an excellent autobiography, Dillard's newest book, For the Time Being,' is a return to nonfiction first-person narrative, the format she used in Pilgrim, and one that best reveals her genius.

Opening with the inquiries - ''Does God cause natural calamity? What might be the relationship of the Absolute to a lost schoolgirl in a plaid skirt? Given things as they are, how shall one individual live?'' - Dillard, who is now writer-in-residence at Wesleyan University in Middletown, Conn., engagingly explores these weighty questions in a series of broken narratives and observations, all organized in a fashion beyond normal convention and expectation.

Such a chorus of voices, such myriad images fill this deceptively slim volume! Her narrative revolves around, and finds inspiration from, several primary touchstones. She repeatedly explores the life and memoirs of paleontologist and naturalistic philosopher Pierre Teilhard de Chardin, the Jesuit who discovered Peking man during a life spent digging in the far reaches of China. She also examines the life of Rabbi Israel ben Eliezer, the Baal Shem Tov, an important 18th-century Hasidic thinker.

Dancing around the stories of Teilhard and Baal Shem Tov are dozens of recurring images of the natural world and human life. Dillard repeatedly marvels at the miracle of human birth while coolly discussing human cruelty and puzzling over a volume that calmly catalogs horrible birth defects. She has chance encounters with Palestinians, observes Chinese peasants, studies people's observations of clouds, muses about the presence of water in the desert and discusses how sand permeates every nook and cranny of the planet. Numbers fills in the gaps: how many humans there are, how many galaxies there might be, how many died in this natural catastrophe or that one. These thoughts and observations constitute the narrative's flow, surfacing, then drifting below, only to resurface again.

While visiting China, Dillard observes the clay soldiers guarding the tomb of Emperor Qin and remarks on how sand and dirt obliterate most human endeavors over time. She strolls through Jerusalem, casting her thoughts back to the words of biblical prophets. Her journeys take her to the obstetrics ward of an American hospital, where she ponders the mystery of birth, seeing the delivery ward as worthy of ritualistic worship and high reverence, a portal on the planet where ''the people come out.'' Each passage is pregnant with meaning, sometimes gently, other times brutally offered for examination.

In addition to this outpouring of personalities, settings and naturalistic themes, Dillard, in her customary fashion, peppers her writing with observations and quotations from scores of writers. Resonating with spirituality, she cites religious thinkers from across time and cultures, including not only her trusty companions Teilhard and the Baal Shem Tov, but biblical prophets, Koranic writers, Jewish leaders, and 20th-century theologians such as Dietrich Bonhoeffer. She refers to Buddhist and Taoist writers, and many of her aphoristic theological references owe much to Eastern thought in how they hang on the page, koan-like, full of mystery and epiphanic possibility.

For the Time Being reverberates with inquiry: Dillard examines, persistently and doggedly, nothing less than the place of God in a world marked by cruelty. Like Pilgrim at Tinker Creek, this new volume is a quest for knowledge, a book that seeks revelation through the study of the world. Perhaps her most illuminating reflection is from Teilhard: By means of all created things, without exception, the divine assails us, penetrates us, and molds us. We imagined it as distant and inaccessible, whereas in fact we live steeped in its burning layers.

Many might find For the Time Being a difficult work to comprehend. If you fail to read carefully, it will be easy to dismiss this book as little more than a laundry list of ideas and facts, observations and anecdotes. Dillard's various narrative elements do not easily weave together to form a common, quickly graspable central thesis, as some may wish they would.

Taken individually, these bits and pieces of the puzzle might appear unconnected and fragmented, like so many individual plants, shrubs and trees. To step back and absorb the scope of Dillard's narrative, however, is to understand how these seemingly disparate elements are revealed as forest: a vast, complex, and remarkably interwoven presentation of the world, a place where ''from time to time anyone may see the vivid veil part,'' revealing the divinity hidden just out of sight.

In this light, For the Time Being is a work of great beauty, a provocative examination of the underlying structure of reality.

It is, in many ways, the fitting successor to Pilgrim at Tinker Creek. As in that book, Dillard is always seeking and musing, while keeping one eye on the world and one toward the heavens. As in Pilgrim, Dillard again couches her reflections in metaphors of light and seeing. ''How can we doubt our own time'' she asks, ''in which each bright instance probes the future? We live and move by splitting the light of the present, as a canoe's bow parts water.''

This volume overflows with such eloquence. The words and thoughts pouring and tumbling off each page pool together magnificently in a well that extends far into the planet while it reflects the heavens above. To drink deeply from these waters is to savor the genius of Annie Dillard's vision.