For much of his career as a Reformer John Calvin was involved in controversy over the doctrine of the Trinity. Not only did these controversies span his career, but his opponents ranged across the spectrum of trinitarian approaches-from staunch traditionalists to radical antitrinitarians. Remarkably, the heart of Calvin's argument, and the heart of others' criticism, remained the same throughout: Calvin claimed that the only-begotten Son of the Father is also, asthe one true God, 'of himself'. Brannon Ellis investigates the varied response to Calvin's affirmation of the Son's aseity (or essential self-existence), a significant episode in the history of theology that is often ignored or misunderstood. Ellis's aim is to explain the historical significance andexplore the theological implications of Calvin's uniquely classical approach to thinking and speaking of the Triune God.