The Trinity, 2:1
HILARY OF POITIERS
He commanded them to baptize in the name of the Father, and of the Son, and of the Holy Spirit: that is, in confession of the Author and of the Onlybegotten and of the Gift. There is one Author of all; for God the Father from whom are all things, is one. And the Onlybegotten, our Lord Jesus Christ, through whom are all things, is one. And the Spirit, the Gift in all things, is one. Everything, therefore, is arranged according to its properties and merits: there is one Power, from whom are all things; one Offspring, through whom are all things; one Gift of perfect hope. Nor will anything be found lacking in that grand perfection in which there is, in Father and in Son and in Holy Spirit, infinity in the Eternal, form in the Likeness, and enjoyment in the gift.The Trinity, 2:1
The Father is he to whom all that exists owes its origin. He is in Christ; and through Christ he is the source of all things. Moreover, his existence is existence in itself, and he does not derive his existence from anywhere else. Rather, from himself and in himself he possesses the actuality of his being.Ibid., 2:6
He is, therefore, the perfect Son of the perfect Father, and the onlybegotten Offspring of the unbegotten God. The Son receives all from him who has all, God from God, Spirit from Spirit, Light from Light. The Son says with confidence: 'the Father is in me, and I in the Father.' For, as the Father is Spirit, so also the Son is Spirit; and as the Father is God, so also the Son is God; as the Father is Light, so also the Son is Light. Those properties, therefore, which are in the Son, are from those properties in the Father.Ibid., 3:4