Augustine of Hippo, one of the most prolific writers of late antiquity, known primarily for four masterpieces: The Confessions, Teaching Christianity, The City of God, and The Trinity, composed a vast body of work comprised of more than five million words. He composed his earliest works in the form of dialogues shortly before his baptism in 387. The next decade of his life, a relatively unproductive transitional period, was followed by an explosion that averaged, in modern terms, a 300-page book per year. This early trilogy, The Happy Life, The Advantage of Believing, and Faith in the Unseen, demonstrates Augustine's fundamental concern to link Christian faith with the human quest for happiness. These three essential works, which illustrate his dictum that faith is necessary for understanding, constitute a magnificent introduction to Augustinian spirituality. Trilogy on Faith and Happiness reveals Augustine's insight into fundamental existential questions and his conviction that human fulfillment can be found only in the incarnation of Jesus, the Word and Wisdom of God. It will prove especially useful for spiritual reading and for students of Christian spirituality.