St. Cecilia's family was one of the principle families of Rome. According to the cultural custom of the time, Cecilia's family betrothed her to a young man named Valerius. On their wedding night, Cecilia told Valerius that she had sworn to remain a virgin before God and that an angel guarded her body, protecting her virginity from violation. She told Valerius that he would be able to see this angel if he went to a certain milestone along the road. Valerius went to the milestone as Cecilia had instructed, and there encountered Pope Urbanus, who instructed the young man and baptized him.
During that era, it was forbidden for anyone to bury the bodies of Christians, so Valerius and his brother dedicated themselves to burying the bodies of all the Christians they found. For this, they were arrested and brought before a judge who ordered them to worship the Roman god Jupiter, and were martyred when they refused to deny thier Christian faith.
The police then came for Cecilia and strongly advised her to renounce her faith. In reply, she told them that she would prefer to die than to denounce the true faith. Upon hearing her response, they brought her to a large oven with the intention of suffocating her with the hot and toxic gasses it emitted.
However, instead of choking, Cecilia began to sing, which is perhaps why she is considered the patron of musicians. Infuriated, her persecutors attempted to behead her, but after three strokes of the sword, Cecilia was still alive and her head was not severed. The soldiers then left her covered in blood in her own home, where she remained for three days before she died.