“Vision,” Margarethe von Trotta’s sympathetic imagining of the life of the 12th-century Benedictine nun Hildegard von Bingen, opens with a prologue that establishes a contemporary secular distance from the film’s devotional medieval ethos. The members of a millennialist sect anticipating their last night on earth prostrate themselves in an abbey overnight only to awaken in the bright morning sun to discover that the world hasn’t ended.

The film is the most recent of several collaborations between Ms. von Trotta, the German feminist director, and Barbara Sukowa, the radiant actress who portrays Hildegard as a mixture of canny politician and fervent mystic who claims to receive messages directly from God. In the film’s sole attempt to visualize an encounter with what Hildegard calls “the living light,” the apparition resembles the CBS logo without the letters.

“Vision” offers a hard-headed view of 12th-century religiosity in which church politics and money conflict with the characters’ asceticism. It portrays Hildegard as a passionate humanitarian and a lover of nature who is shocked and disgusted by the mortification of the flesh through rituals like self-flagellation and extreme fasting....