For nearly 2,000 years, Christian mystics, martyrs, and sages have documented their search for the divine. Their writings have bestowed boundless wisdom upon subsequent generations. But they have also burdened many spiritual seekers. The sheer volume of available material creates a seemingly insurmountable obstacle. Enter the Upper Room Spiritual Classics series, a collection of authoritative texts on Christian spirituality curated for the everyday reader. Designed to introduce 15 spiritual giants and the range of their works, these volumes are a first-rate resource for beginner and expert alike. Living in turbulent 14th-century Italy, Catherine was driven to submit her will completely to God's will for her. Her intense prayer life led her to write hundreds of letters to friends, other monastics, and heads of state, urging them to turn away from sin and draw closer to God. Catherine's life of total prayer has long inspired admiration.