What if anything can human beings know about God, either by way of philosophical reasoning or by divine revelation? How does the mystery of the Incarnation illuminate our understanding of the nature and mystery of God and the nature and destiny of the human person? The essays in this book explore topics pertaining to the nature of God, apophatic theology, divine simplicity and the holy Trinity, divine beauty, and the beauty of creation. The book also contains a series of speculative considerations of Christology: Why did God become human? How ought we understand the two natures of Christ and the topic of the communication of idioms (attribution of both divine and human properties to one person)? There is also a sustained treatment of Jesus' human knowledge and voluntary freedom. Did Jesus understand his own lordship and his unity with the Father and the Holy Spirit, and if so, how? Did Christ's human will always accord with the divine will, and what significance does this idea have for our understanding of the redemption affected by Christ for the whole human race? Through these explorations, principles drawn from Thomas Aquinas and from Thomistic tradition are taken into account as key resources for the adjudication of contemporary theological challenges. Principles of Catholic Theology, Book 3 is a continuation of Fr. Thomas Joseph White, OP, collection of essays, extending over a range of fundamental topics in Catholic dogmatic theology.