Last spring I wrote a column about Hildegard of Bingen, the "medieval mystic superstar" who, a mere 833 years after her death, was finally officially inscribed in the Catholic Church's record of saints this past May. On October 7 of this year, Hildegard—along with a relatively unknown 16th-century Spanish mystic called John of Avila—will be designated a "Doctor of the Church," meaning that her writings are officially endorsed by the Catholic Church as having made a particularly important contribution to theology and Christian doctrine.

I cannot presume to explain why Pope Benedict or his advisors want to elevate Hildegard at this time. Perhaps he is merely taking care of "one of his own"; the pope, after all, hails from Bavaria, less than 300 miles from the Rhine valley where Hildegard lived. In some ways Hildegard's writings affirm a truly conservative understanding of church hierarchy and theology, which no doubt would appeal to the current pontiff. But in other ways, Hildegard is truly a visionary, not only by the literal fact of her mystical experiences, but in how her understanding of the place of art in the life of faith, the role of women in the church, and the importance of spiritual experience, all point to a figure whose contribution to Christianity has the potential of creating real transformation—even after almost a millennium.

Perhaps one way to ponder the singular nature of Hildegard's vision is to consider one of her visions. When Hildegard began recounting her visionary experiences in what eventually became her first book, Scivias ("Know the Ways"), her writings were accompanied by vivid, colorful illustrations which some scholars believe she was involved on some level in producing—perhaps providing instruction to the artist(s). But even if these illuminations were not created under Hildegard's direct influence, they nevertheless are based on the detailed descriptions of her visions found in her own words. So, like William Blake over 600 years later, Hildegard's legacy includes not only writings about mystical experiences but colorful illustrations that make her visions truly come alive.

One of those visions (the second one recorded in Scivias) depicts Christ as a sapphire blue figure, standing in the midst of two circles: one golden-colored, its diameter just about the same length as Christ's height; the other, larger one a lighter color, surrounding and enfolding the smaller figure. These circles, in turn, are surrounded by a blue background and a framework of floral designs. This striking image, according to Hildegard, is not just of Christ, but indeed is a vision of the Holy Trinity.

"This is the perception of God's mysteries . . . that bright light bathes the whole of the glowing fire, and the glowing fire bathes the bright light; and the bright light and the glowing fire pour over the whole human figure, so that the three are one light in one power of potential." So writes Hildegard of her vision. In short, the largest circle represents light—the light of God. The inner circle signifies the fire of the Holy Spirit. And of course, the figure, washed in a rich, watery blue, is Christ; not a lonely, bereft Christ but rather, Christ embedded in the fire of the Spirit and the light of the Creator.

It's a circular, cyclical, mandala-esque Holy Trinity. Forget those silly diagrams of Triangles your Sunday School teacher used to try to make this mysterious doctrine comprehensible. Instead of the sharp, angular (and hyper-masculine) triangular Trinity, Hildegard offers a fluid, energetic, embedded, holistic Trinity that eschews anthropomorphism for the Father and the Spirit but celebrates both the distinctiveness of the three persons and their inherent unity.