“This Saint was a prominent actress of the city of Antioch, and a pagan, who lived a life of unrestrained prodigality and led many to perdition. Instructed and baptized by a certain bishop named Nonnus (November 10), she departed to the Mount of Olives near Jerusalem, where she lived as a recluse, feigning to be a eunuch called Pelagius. She lived in such holiness and repentance that within three or four years she was deemed worthy to repose in an odour of sanctity, in the middle of the fifth century. Her tomb on the Mount of Olives has been a place of pilgrimage ever since.” (Great Horologion). The Prologue adds that Pelagia had accumulated a large fortune as a courtesan, all of which she gave away to the poor upon her conversion.

She lived in Alexandria, where, when she was seventeen, her own mother placed her in a brothel, where due to her great beauty she was able to amass some wealth. Saint Serapion (March 21), hearing about Thaïs and her way of life, was moved by God to try to convert her. He dressed himself as a soldier, found her, gave her a gold piece, and went with her to her room. When the door was shut, he put aside his tunic, revealing his monastic robe, and asked if he might speak with her. With tears he told her of the doom that awaits sinners, and of the infinite mercy of God, who desires that all should be saved and welcomes every repentant sinner. Thaïs, her heart melted by his words, ran to the public square, burned all the fine clothes and possessions that she had acquired through her trade, and went with Serapion to a women’s monastery. There he instructed her to stay secluded in her cell, beseeching God’s mercy constantly and only eating every other day; she was to do this until she was instructed otherwise. Thaïs lived in this way for three years, with such zeal that she amazed all her monastic sisters. Meanwhile St Serapion went to St Anthony the Great to ask him if God had accepted Thaïs’ repentance. Saint Anthony and his brethren spent a night in prayer and received a vision in which they were assured that Thaïs had been found worthy of God’s mercy. Returning to the monastery, Serapion made the repentant Saint leave her cell, though by now she only wished to spend her life in repentant prayer. After spending only fifteen days in the common life of the monastery, the holy Thaïs reposed in peace.