This book offers a definitive exploration of one of Christianity's most profound mysteries — how divine grace and human freedom coexist within the journey toward salvation. Drawing on the timeless insights of Thomas Aquinas, this richly detailed volume unpacks his masterful synthesis of theology and philosophy, revealing how grace empowers but never overrides free will, and how God's providential care orders human choices toward ultimate fulfillment.

Blending historical context, rigorous analysis of primary texts, and engagement with centuries of theological debate, the book guides readers through the essential doctrines of justification, merit, predestination, and the beatific vision. It addresses longstanding controversies such as Pelagianism and semi-Pelagianism, and demonstrates Aquinas's enduring relevance for contemporary theology, spirituality, and philosophy of freedom.

Perfect for scholars, clergy, and serious students of theology, this book illuminates the dynamic interplay between God's sovereign grace and genuine human freedom — a relationship that shapes the Christian understanding of morality, salvation, and the deepest longings of the human heart. With accessible yet erudite prose, it invites readers into a transformative journey through grace, offering clarity on complex doctrines and inspiring a renewed appreciation for the mystery of salvation as a divine-human partnership.