Eudocia was from Heliopolis of Phoenicia (now Baalbek in Lebanon). A surpassingly beautiful pagan, she led a licentious life and became wealthy from the gifts of her many lovers. One day an elderly monk, Germanus, came to Heliopolis and stayed with a Christian whose house adjoined Eudocia's. At night, he began to read aloud from the Psalter and a book on the Last Judgment. From next-door, Eudocia heard him. Her heart was reached, and she stood attentively all night, listening to every word in fear and contrition. The next day she begged Germanus to visit her, and he explained the saving Christian faith to her. Finally, Eudocia asked the local bishop to baptise her. She freed her servants, gave all her wealth to the poor, and entered a monastery.

"Her former lovers, enraged at her conversion, her refusal to return to her old ways, and the withering away of her beauty through the severe mortifications she practiced, betrayed her as a Christian to Vincent the Governor, and she was beheaded"(Great Horologion). According to some,this was under Trajan (98-117); according to others, under Hadrian (117-138).

The Prologue gives a somewhat different account: that after entering the monastery, Eudocia was permitted to pursue the monastic life in peace — with such devotion that, thirteen months after she entered the monastery, she was chosen as abbess. She lived for fifty-six years in the monastery, and was granted the gift of raising the dead. In her old age, a persecution of Christians arose, and Eudocia was beheaded along with many others. "Here is a wonderful example of how a vessel of uncleanness can be purified, sanctified and filled with a precious, heavenly fragrance by the grace of the Holy Spirit" (Prologue).