Throughout her life, Hildegard of Bingen followed her own spiritual inclinations. Despite her young age and gender, she was open to the visions granted her from the Divine Spirit, and she crafted her life around their teachings. Her wisdom and holiness were eventually rewarded with leadership over the nuns at her home, the monastery of Disibodenberg when her Abbess died. Even the Pope eventually came to read of her visions and declared them perfectly inspired of God. Yet shortly thereafter, she received a new visionary call, to move her 20 or so nuns from Disibodenberg down the Rhine to a new home at Rupertsberg. The move threatened the nuns themselves with hardship (physically raising a new cloister) and her male superiors with decreased income (by losing the nuns' inheritances) and fame (with Hildegard herself leaving). Yet she followed that inner voice and founded a new abbey on nearby lands dedicated to St. Rupert, the saint who was believed to have first brought the Gospel to Bavaria (and may also have been the first to mine salt in Salzburg). She wrote at last three antiphons in honor of the saint, for singing during the liturgical Office on his feast day, including O felix apparicio.
Hildegard's Latin text for O felix apparicio is redolent with images of growth -- appropriate both to the saint's historical position as founder of Bavarian Catholicism, and to her own experience of founding a new ecclesiastical institution in Bavaria. She compares Rupert to a "fruitful apparition," one in whom the "flame of life gleamed" and in whose heart both the love and fear of God moved; Rupert's knowledge of God then "flowered" into the "supernal city." Hildegard's music begins with a melodically understated opening, centered on the Phrygian tonic of E, and only escapes the close melodic orbit as her text utters the name of Rupert. The "glittering flame of God" is sung in this now-expanded melodic range, but once again she breaks the melodic bounds and gradually fills the complete melodic space when setting the "love of God." The music for the "supernal city" leaves the modal grounding almost reluctantly, but the final word of the text -- "flowered" -- appropriately receives the greatest and most florid melisma of the entire composition, gradually cresting through the complete modal range to the highest pitch of the chant, and just as gracefully falling back down through the most important pitches to the tonic.