Published posthumously in 1588, “The Interior Castle” was written over several weeks in 1577 by Saint Teresa of Avila, a prominent 16th century Spanish mystic, Carmelite nun, theologian, and writer of the Counter Reformation. Saint Teresa of Avila was born in 1515 in Avila, Spain to a wealthy and prominent family. After the death of her mother when she was 11, she went to live with the Augustinian nuns and devoted the rest of her life to the church until her death in 1582. “The Interior Castle” was written shortly after Saint Teresa finished her autobiography, “The Life of Saint Teresa of Avila by Herself”, which has become a classic work of Christian mysticism. Saint Teresa wrote “The Interior Castle” to guide the faithful in their spiritual development and relationship with God through service and prayer. Inspired by a vision she received of the soul as a diamond in the shape of a castle containing seven mansions, Saint Teresa interpreted this vision as the journey of faith in seven stages, culminating in the perfect union with God. This classic masterpiece of faith and devotion remains an inspiring and helpful guide to those seeking a deeper spiritual practice.