4 To go on with my story, her ways were quiet and she lived in great privacy. In fact, she rarely went abroad or spoke to a man. More wonderful still, much as she loved her virgin sister, she did not care to see her. She worked with her own hands, for she knew that it was written: “If any will not work neither shall he eat.” To the Bridegroom she spoke constantly in prayer and psalmody. She hurried to the martyrs' shrines unnoticed. Such visits gave her pleasure, and the more so because she was never recognized.
All the year round she observed a continual fast, remaining without food for two or three days at a time; but when Lent came she hoisted— if I may so speak— every stitch of canvas and fasted nearly from week's end to week's end with “a cheerful countenance.” What would perhaps be incredible, were it not that “with God all things are possible,” is that she lived this life until her fiftieth year without weakening her digestion or bringing on herself the pain of colic. Lying on the dry ground did not affect her limbs, and the rough sackcloth that she wore failed to make her skin either foul or rough. With a sound body and a still sounder soul she sought all her delight in solitude, and found for herself a monkish hermitage in the centre of busy Rome.
Source: Letters (New Advent)