Pope Benedict's approach to encyclicals is different from that of his predecessor Pope John Paul II.
He is more inclusive in his sources, drawing on non-Christian authors, philosophers, and novelists among them, as well as more traditional works.
His encyclicals also differ from his typical theological works; they are more pastoral, at times even conversational, inviting the reader into the mystery of the three theological virtues that frame and inform the Christian life.
Deus caritas est explores a God who is both reason (logos) and love, and who loves us passionately, reclaiming eros as a descriptor of God's love.
Spe salvi examines the relation between faith and hope, arguing that without faith and its vision of God's justice, hope too easily substitutes a secular idea of progress that often leads to atheism.
Lumen fidei, drafted for his successor, Pope Francis, focuses on faith as a light flowing from a personal relationship with God.
The book notes how the three encyclicals were received and concludes with reflections on Pope Benedict's theological legacy.