Having thus lost out on becoming the empire's first lady, Kassia built a convent on Xerolophos, Constantinople's seventh hill. There she took the veil and was tonsured a nun. Until her death sometime in the second half of the ninth century Kassia lived in this cloister which bore her name, "leading a philosophical life pleasing to God."
The foundress of the cloister was also the first lady, a strict, vigilant and energetic abbess. The abbess governed her nuns, regulated life and worship in the convent and still found time to pursue her literary interests. Kassia's writings include both secular and sacred poetry. They survive in a number of manuscripts dating from the 11th to the 16th century.
The secular writings project the forthright personality of a woman wise in the ways of the world. A sharp-tongued observer of human frailties, Kassia had strong convictions and dislikes. These she expressed tersely in a series of seven statements all of which begin with Miso—I hate. Kassia scorned pretense of all kinds, "I hate the fool who acts the philosopher," she wrote, and "I hate the rich man who groans that he is poor." She despised time-servers: "I hate the person who is forever changing his ways." She condemns those who unlike God (Acts 10:34) discriminate among people: "I hate the judge who is a respecter of persons."
Kassia's sacred poetry made her Byzantium's, and indeed Christendom's, only woman hymnographer of distinction. For centuries her name automatically has appeared on all lists of Byzantine liturgical poets. In the first such known list, drawn up in the 14th century by Nikephoros Kallistos Xanthopoulos, himself a hymnographer, Kassia is mentioned last, one of the eleven most distinguished Greek hymnodists. She enjoys such prestige that 37 hymns of uncertain authorship, including the Akathistos Hymnos, have been attributed to Kassia in manuscripts and liturgical books.
Likewise Kassia is Byzantium's best known woman composer. A gifted composer, this hymnwriting abbess wrote original musical settings for most of her hymns. She is therefore properly called Melodos". Later other church poets borrowed her music for their hymns.
The surviving 23 genuine hymns indicate Kassia's interest in many aspects of the Church's liturgical cycles. She provided the services of her convent with many new hymns. Signed by her name, Kassias, the kanon for the dead is her longest hymn. Its 32 strophes were composed to be sung in the convent's cemetery during memorial services held on Saturday. Her shorter hymns, stichera, represent her lyric and dramatic genius. These monostrophic compositions include hymns honoring the saints, some obscure like Saints Gurias, Samonas and Abibus (November 15), others more prominent like the Apostles Peter and Paul, or John the Baptist for whom she composed four stichera. In nine joyful hymns, including the majestic Avgoustou monarchisantos ("When Augustus ruled"), she celebrates Christmas, the coming of Christ into the world.She also wrote three hymns for the Feast of the Presentation of Christ in the Temple (February 2) with which the Nativity cycle ends.
Kassia's reputation rests primarily on her troparion for Holy Wednesday. This penitential hymn for which Kassia composed the music, has been hailed by critics as a masterpiece of religious poetry, admired for its beauty of words and depth of feeling. A true poet, Kassia in this short hymn portrays profound human emotions and experiences. In the figure of the sinful woman, whose story Luke (7:36-50) introduced into Christian literature, Kassia traces with feminine grace and sensitivity the Lenten journey of repentance, the soul's exodus from sin to salvation. The Byzantine nun does not condemn the sinner. Rather she sings a new song, celebrating the sinful woman's intuition, her recognition of Christ's divinity and her pursuit of holiness.
The abbess translates into poetry, into words of haunting beauty and truth, the speechless tears of the erring woman in the Gospel story. Except for a brief introductory passage, the troparion consists of an intensely dramatic monologue. It begins with the woman's confession, in which she admits guilt and responsibility for her moral degradation:
For night holds me in its grip, the goad of lust, a murky and moonless love of sin.
Then through passionate sequences of petitions to the Lord she moves towards redemption, led from darkness to light by Christ.
who has great mercy beyond all measure
In the end the repentant sinner finds hope, forgiveness and peace.
Across the more than 10 centuries which separate us from the Byzantine nun, Kassia the Melodos communicates the reality of the Christian passover from death to life, as well as her serene belief in the transforming grace of divine philanthropia.