In 1826, Sister St. Theodore was given the daunting task of serving as the superior of St. Aubin Parish at Rennes. This part of the city was filled with devastatingly poor and unchurched people – victims of the aftermath of the .
For four years, Sisters of Providence of Ruillé had tried to assist the people but without success. With the appointment of Sister St. Theodore, things began to slowly change. Little by little, the children became disciplined and learned their religious instructions. This change in the children had far-reaching effects upon the entire parish
In 1834, Sister St. Theodore was named the superior of Soulaines in the Diocese of Angers. In this small parish, Sister St. Theodore continued her teaching and also visited the sick. She was an excellent teacher and was recognized by the Academy of Angers for her pedagogical skills. However, it was through her visitation of the sick that a whole new world was opened to her as she learned the basics of medicine and remedies from a local doctor. It was also while she was in Soulaines that her spiritual life deepened. Sister St. Theodore remained at Soulaines until 1840.French Revolution