from the Synaxarion:
The Nun Taisia, raised by her mother in a spirit far removed from Christian piety, led a depraved and dissolute life. She was famed for her beauty, alluring many on the path to sin.
The account about the prodigal Taisia spread throughout all Egypt and reached even the Elder Paphnutios, a strict ascetic who had converted to salvation many of the lost. Dressing himself in worldly attire, Elder Paphnutios went to Taisia and asked her to name for him a place where not only people but even God Himself would not see them. Taisia answered that this was impossible, since God is omnipresent everywhere, and He sees and knows all. Having seen in her soul the spark of the fear of God, the Elder went further. He pointed out all the grievousness and loathesomeness of her sins, and he told her about the answering she would have to give before God for the souls of people corrupted and destroyed by her.
The words of Saint Paphnutios so affected the sinner that she, having gathered up all her riches acquired by her shameful manner of life, then set them afire in the city square and withdrew with the Elder to a monastery, where for three years she dwelt in seclusion. Having turned herself towards the East, Taisia incessantly uttered the short prayer: "My Creator, have mercy on me!"
"From that minute, when I entered into the cell, all my sins constantly were before my eyes, and I burst out in tears in remembering them," said the Nun Taisia to the Elder before her death. "It is for this, thy tears, and not for the austerity of thy seclusion that the Merciful Lord hath granted thee mercy," said Saint Paphnutios in answer to her.
Thus the life of St. Taisia proved the prophet's words, "a heart that is broken and humbled God will not despise." [Psalm 50/51]