Sophia Lang was born in Lucerne, Switzerland on May 12, 1884. Left an orphan at an early age, she was raised by a single brother and sister, who lived in the country. They were very poor and Sophia helped with the farm work, though never very robust. She was subject to fainting spells, and for a time lost her voice. As she had a strong desire to become a Sister, she made a pilgrimage to the Shrine of the Black Madonna at Einsiedeln, where she was cured. 

She immigrated to America in 1900 at the age of 16, and entered the Clyde convent five years later, on Nov. 2, 1905. She was invested with the Benedictine habit on July 14, 1906, made her first profession on Sept. 27, 1907, and perpetual vows on July 5, 1913. Sister was one of the large group to receive Consecration of Virgins in 1952.

Sister M. Prisca had only seven years of formal schooling, but was very intelligent and added much to her store of knowledge through reading and study. She helped in the printery and for many years set the type for Tabernakel und Fegefeuer - a task which she fulfilled with utmost care and devotedness. After the German edition was discontinued, she helped with other work at the printery. Later confined to the infirmary, Sister spent many hours each day, neatly counting out and folding leaflets for the Correspondence Department.

Throughout her religious life Sister was an example of faithful observance, attending all community exercises as long as she was able, and taking her turn faithfully at adoration, both by day and night. In the course of years Sister became totally deaf, an affliction which caused her much distress but which she bore with utmost patience and cheerfulness. In spite of this handicap, she would always go to the conferences and to community recreations, happy to be with the Sisters even though her communication was limited to writing or gestures. In later years she was provided with a magnetic writing pad which was a great help to her. 

Sister never missed reading a note on the bulletin board, or a community newsletter or any of the spiritual exhortations given by the superiors. She often expressed her gratitude to the superiors for all that was done for her, in notes such as this: "I am overflowing with acts of charity from our Sisters and will try every day anew to love Jesus more, and to offer as much as I can for the Sisters and nurses. I am happy, really in joy and peace, trying to pray and be united with Jesus and offer everything as best I can to Him for souls.”

Sister M. Prisca seemed to have had a stroke some years before her death and gradually became more and more stooped. She was often at death's door, and finally answered God's summons on the feast of Our Lady of Mt. Carmel, July 16,1971, in the 88th year of her life.