The Father is revealed by the Son, that is, by His Word. For if the temporal and transitory word which we utter both shews itself, and what we wish to convey, how much more the Word of God by which all things were made, which so shews the Father as He is Father, because itself is the same and in the same manner as the Father.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: De Trin., vii, 3