The Trinity. Translated by Stephen McKenna, C.SS.R. [The Fathers of the Church. A New Translation, No. 25]

During the years between the Council of Nicaea (325) and the Council of Constantinople (381), imperial opposition to Nicene theology sent several of its supporters into exile. One of these supporters was Hilary, the Bishop of Poitiers. Begun during its author's exile (356-360), Hilary's De Trinitate provides a comprehensive discussion of the relationship between God the Father and God the Son: they are consubstantial, co-eternal, and fully equal. This work was a trailblazer in its day because, apart from Tertullian's relatively brief remarks on the Trinity, it is the earliest study of Trinitarian doctrine in the Latin language.