The word mystic does not bring to mind edifying images for most Christians these days. It smacks of a vapid, Southern California mindset, readily exploited by marketers of tea and juice and such. For the more historically minded, mystic might suggest the wild–haired, unwashed visionaries off in the wilderness—not, in other words, something of much concern to everyday believers as they balance their finances or play catch with their kids.

But true mystics are far from amorphously spiritual. As Bernard McGinn has put it, "no mystic (at least before the present century) believed in or practiced 'mysticism.' They believed in and practiced Christianity (or Judaism, or Islam, or Hinduism), that is, religions that contained mystical elements as part of a wider historical whole." McGinn's work serves as the starting point for William Harmless, a professor of theology at Creighton University, whose new book Mystics is a walk through the lives and teachings of eight great mystics: Thomas Merton, Bernard of Clairvaux, Hildegard of Bingen, Bonaventure, Meister Eckhart, and Evagrius Ponticus from the Christian tradition, as well as the Sufi poet Rumi and the Buddhist divine Dogen.

Harmless opens the book by presenting two contrasting views of mysticism. In the early 15th century, Jean Gerson, chancellor of the University of Paris, wrote a two-volume treatise on the subject, the first scholarly study of mysticism. The title alone, On Mystical Theology, shows his view: Mysticism is theology, but more personal and experiential than the scholastic theology of the academy. Gerson defines this mystical theology as "an experiential knowledge of God that comes through the embrace of unitive love," and he offers a robustly evocative account of the mystics' writings: "They talk of a jubilation beyond the spirit, of being taken into a divine darkness, of tasting God, of embracing the bridegroom, of kissing him, of being born of God, of obeying his word, of being brought into the divine cellars, of being drunk in a torrent of delight, of running into an odor of his perfumes, of hearing his voice, and entering into the bedroom, and of finding sleep and rest in peace with him."

A second approach is represented by the modern American philosopher William James and his enormously influential Gifford lectures, published under the title The Varieties of Religious Experience. James believed religion to be a matter of personal experience, not ideas: "The mother sea and fountain-head of all religions lie in the mystical experience of the individual." The sacred history, tradition, scriptures, and rituals of particular religions are all local outgrowths from this universal experience, and are not necessary for understanding it. At first glance, James' approach may appear to be quite similar to Gerson's: both emphasize the experiential character of mysticism. But for James, in contrast to Gerson, theology is strictly epiphenomenal.

Harmless' own view is squarely, though respectfully, opposed to James'. Indeed, he writes, "James treats history as though it were a stream to be stepped over instead of an ocean we swim in." As Harmless leads readers through the writings of his eight mystics, he gives the context surrounding each author's writing and shows how necessary that context—in all its ritualistic, theological, and historical fullness—is for understanding mysticism.

Four of these mystics seem especially noteworthy. Harmless begins with Thomas Merton, perhaps the best-known mystical writer of the 20th century—and the most accessible, if least deep, of the mystics he surveys. Merton attended Cambridge University for a year before being sent down for doing more partying and drinking than studying, and also for fathering a child out of wedlock. After Cambridge, Merton returned to America and completed his education at Columbia, where he was baptized a Catholic. Merton set out to be a professional writer, but soon entered a Trappist monastery in Kentucky. While in the monastery, Merton continued to write, and beginning with his autobiography The Seven Storey Mountain his books became famous. In his early writings, Merton focuses on Catholic theology, advocating the practice of contemplation in a world filled with noise. For Merton, contemplation is "a sudden gift of awareness," and the quest for holiness is "the quest for one's true face" as seen in the face of God. Merton's concept of prayer, Harmless writes, "centers on 'presence'; it presumes and builds on faith; it praises without words and adores without gesture. It comes up out of the 'center'—which presumes, of course, that one has found that interior center amid the swirl of one's inner consciousness."

Later in life, Merton became more interested in writing on themes of social justice and Eastern spirituality. He even traveled to the East, an extreme rarity for a Trappist, where he had an intense mystical experience while praying before the statue of the Buddha at Polonnaruwa. In the eyes of this reviewer, this marks a distinct departure from the intense, orthodox Catholicism of his early years. There appears to be a difference between the earlier and the later Merton, but Harmless makes no distinction between the two. He concludes with a passage from Merton's The Sign of Jonas, in which Merton writes of watching for fires on the monastery property one summer evening. The experience, says Harmless, captures Merton as a fire-watcher standing outside modern culture, testifying to the broken nature of the human heart and pointing the way for broken men to be made whole.

Harmless then introduces the reader to Bernard of Clairvaux, the great Cistercian abbot—and celebrity—of the 12th century. Bernard traveled throughout Europe founding monasteries, preaching two crusades, engaging in academic and ecclesiastical controversies, and advising popes. But his greatest legacy can be found in his writings. In On Loving God, Bernard shows how the human desire to love God comes as a response to the love of God.

In his sermons on the Song of Songs, Bernard explores the love of God further. Harmless writes, "Bernard was convinced that the Song of Songs' central theme—the passions and love play of the wedding night—provides the best analogy for describing the human encounter with the divine. The claim is breathtaking. We today use the term 'mystical marriage' without thinking how astonishing it is to claim that God and a human being can so unite as to be married." While reading Bernard, one is not only moved by the power of his message but also struck by the fact his prose is full of references to sacred Scripture. It is obvious that Bernard was a man who studied and soaked in the words of the Bible and the fathers of the Church, and that one cannot peel away their influence from the core of his writing.

A century after Bernard, a German Dominican named Meister Eckhart was preaching on the nature of God. Eckhart was famous, and controversial, for using strong language to jolt his listeners out of their human conceptions of God. He attacked traditional religious language and names for God, and also diminished the distinction between man's being and God. For such preaching, Eckhart was accused of heresy during his own lifetime and after death. It is probably Harmless' greatest work of pedagogy that he makes Eckhart's writing understandable, and that he shows how Eckhart's radical theology was not heretical as many took it to be.

Eckhart conceived of God's inner life as "a 'boiling,' a giving birth to itself—glowing in itself, and melting and boiling in and into itself, light that totally forces its whole being in light and into light and that is everywhere turned back and reflected upon itself." In other words, "God is an inner bursting creativity that spills over as joy, as exuberance, as beauty: 'God delights in himself. In the delight in which God delights in himself, he delights also in all creatures.' " From this lively emanation present in the Trinity emanates creation itself, and therefore all creation ultimately has at its core the same being, that of God. By saying this Eckhart is not embracing monism, but rather reminding the hearer of the full implications of the words "in him we live, and move, and have our being."

Dogen was a similarly controversial figure in 13th-century Buddhism, the founder of the Soto sect. His primary teaching was the practice of zazen as a means "to drop off body-mind." One would sit without thinking, but also without not-thinking. Instead, one would practice nonthinking. Once again, Harmless is adept in deciphering what this might mean: "Nonthinking, it seems, lies beyond both thinking and not-thinking; it 'neither affirms nor denies, accepts nor rejects, believes nor disbelieves'; it is presencing, a realizing of the 'pure presence of things as they are.' " This kind of mystical practice, Dogen teaches, would reveal true human nature and give its practitioner an experience of what Harmless calls "ultimate reality." So far Dogen's teaching aligns with traditional Buddhist doctrines, but he departs from them in his definition of what has sacred dignity—what is known in Buddhism as "Buddha-nature." Christians limit sacred dignity to human beings, and traditional Buddhists limit Buddha-nature to sentient beings, but Dogen extends it to all things. In other words, everything has an innate holiness. Traditional Buddhism also teaches that one should flee the impermanence of the world and seek the purity of Buddha-nature, which does not change. Dogen, however, teaches the exact opposite: the world in its impermanence is Buddha-nature.

At this point the reader is justified in wondering how Dogen could be categorized as mystic in the same vein as Bernard of Clairvaux. If we think of mysticism as the soul's union with God, or as an exploration of the natures of God and man—Harmless' preliminary definition of mysticism—then Dogen is not a mystic. But if you broaden the definition of mysticism, as Harmless does in his conclusion, to include profound experiential knowledge of God or of ultimate reality, Dogen and Bernard fall into the same category. The fact remains, however, that the Christian conception of knowing a personal God and the deity-free Buddhist conception of realizing Buddha-nature are markedly different. Indeed, Harmless says that his goal is "to take up and to take on the widespread claim that 'all religions are all the same at the top,' that 'mystics are all experiencing the same thing.' … I hope I've shown here … that such claims are simply nonsense, that those who make them have simply not done their homework." Harmless has shown this well, but he leaves the reader wanting to know more about how Buddhist and Christian mysticism differ.

That aside, Mystics accomplishes everything Harmless sets out to do. With miraculous clarity, Harmless leads the reader through the select mystical texts and ends by reiterating what the reader now already knows: mystics cannot be separated from the scriptures, liturgy, communities, and history that formed them. Mysticism may be experiential theology, but it is still theology. In making that case with such lucidity, William Harmless has provided the lay reader with an outstanding introduction to the great mystics and their writings.

Nathaniel Peters is a junior fellow at First Things.

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