Cecilia, a virgin of a senatorial family and a Christian
from her infancy, was married by her parents to a noble
pagan youth Valerianus. When the couple had retired to
the wedding-chamber, Cecilia told Valerianus that she was
betrothed to an angel who jealously guarded her body;
therefore Valerianus must not violate her virginity.
Valerianus wished to see the angel, whereupon Cecilia
sent him to the third milestone on the Via Appia where
he should meet Pope Urbanus. Valerianus obeyed, was
baptized by the pope, and returned a Christian to Cecilia.
An angel then appeared to them and crowned them with roses
and lilies. Tiburtius, the brother of Valerianus, was also
won over to Christianity. The brothers distributed rich
alms and buried the bodies of the confessors who had died
for Christ.
The prefect, Turcius Almachius, condemned them to death; an officer of the prefect, Maximus, appointed to execute this sentence, was himself converted and suffered martyrdom with the two brothers. Their remains were buried in one tomb by Cecilia.
Then Cecilia herself was sought by the officers of the prefect. Before she was taken prisoner, she arranged that her house should be preserved as a place of worship for the Roman Church. After a profession of faith, she was condemned to be suffocated in the bath of her own house. As she remained unhurt in the overheated room, the prefect had her decapitated there. The executioner let his sword fall three times without separating the head from the trunk, and fled, leaving the virgin bathed in her own blood. She lived three days, made dispositions in favour of the poor, and provided that after her death her house should be dedicated as a church. Urbanus buried her among the bishops and the confessors, i.e. in the Catacomb of Callistus.
The time when Cecilia suffered martyrdom is not known. The only time-indication is the position of the tomb in the Catacomb of Callistus, in the immediate proximity of the ancient crypt of the Popes, in which Urbanus probably was buried.
The oldest representations of St. Cecilia show her either with the crown of martyrdom in her hand or in the attitude of prayer. In the apse of her church in Trastevere is still preserved the mosaic made under Pope Paschal, wherein she is represented in rich garments as patroness of the pope.
Since the fourteenth and fifteenth centuries she is represented as playing on the organ, evidently to express what was often attributed to her; that while the musicians played at her nuptials she sang in her heart to God only. Possibly the cantantibus organis was erroneously interpreted as Cecilia herself as the organist. In this way the saint associated with music. When the Academy of Music was founded at Rome (1584) she was made patroness, whereupon her veneration as patroness of church music in general became still more universal.
Her feast is celebrated in the Latin and the Greek Church on 22 November.