How do Christians understand the Trinity? How does this understanding relate to other Christian teachings? In conversation with key thinkers in contemporary and classical theology, particularly Henri de Lubac, Karl Rahner, Thomas Aquinas and Augustine, this book argues that a theology of symbols can help us glimpse the mystery of the Trinity and see how this central Christian teaching corresponds to Christian understandings of creation, humanity and the church. A symbol is not here understood as an arbitrary sign, but as a sign that mediates the presence of the symbolized. Joshua Mobley examines the understanding of the Father as "symbolized" in the Son who is the "symbol" of the Father by the "symbolism" of the Spirit, the personal agent of unity between Father and Son. These trinitarian relations then structure creaturely relations to God: God is symbolized in creation, which is a symbol of God by participation in the Son, and the church is symbolism, the union of creation with God by the power of the Spirit. Mobley thus argues that a theology of symbol helps coordinate trinitarian theology with key themes in Christian dogmatics.