Against the Arians: Texts Explained; Seventhly, John xiv. 10. Introduction. The doctrine of the coinherence. The Father and the Son Each whole and perfect God. They are in Each Other, because their Essence is One and the Same. They are Each Perfect and have One Essence, because the Second Person is the Son of the First. Asterius's evasive explanation of the text under review; refuted. Since the Son has all that the Father has, He is His Image; and the Father is the One God, because the Son is in the Father · Theoria