The biographical sketch about Mother Theresia Messner aims to serve as an introduction to her inspiring life and her rich personality and achievements. A reader journeys through her childhood, first steps in Steyl, years as the novice directress, an appointment as a First Superior General of the Missionary Sisters, Servants of the Holy Spirit, until her death. The book contains testimonies and memories of the first sisters interviewed by Sr. Sixta Kasbauer who wrote the biography of Mother Theresia. Letters, personal memories and notes of Mother Theresia are a great treasure. They show her inner greatness and deep spirituality. Like her great patroness, Teresa of Avila, Mother Theresia could not have achieved all she did nor would she have meant so much to the sisters if she had not been a deeply prayerful person, one who truly walked in the presence of the Lord.