4 For consider, all you who invent such opinions, since the Father Himself is alone called God, who has a real existence, but whom you style the Demiurge; since, moreover, the Scriptures acknowledge Him alone as God; and yet again, since the Lord confesses Him alone as His own Father, and knows no other, as I shall show from His very words, — when you style this very Being the fruit of defect, and the offspring of ignorance, and describe Him as being ignorant of those things which are above Him, with the various other allegations which you make regarding Him—consider the terrible blasphemy [you are thus guilty of] against Him who truly is God.
You seem to affirm gravely and honestly enough that you believe in God; but then, as you are utterly unable to reveal any other God, you declare this very Being in whom you profess to believe, the fruit of defect and the offspring of ignorance. Now this blindness and foolish talking flow to you from the fact that you reserve nothing for God, but you wish to proclaim the nativity and production both of God Himself, of His Ennœa, of His Logos, and Life, and Christ; and you form the idea of these from no other than a mere human experience; not understanding, as I said before, that it is possible, in the case of man, who is a compound being, to speak in this way of the mind of man and the thought of man; and to say that thought (ennœa) springs from mind (sensus), intention (enthymesis) again from thought, and word (logos) from intention (but which logos? for there is among the Greeks one logos which is the principle that thinks, and another which is the instrument by means of which thought is expressed); and [to say] that a man sometimes is at rest and silent, while at other times he speaks and is active. But since God is all mind, all reason, all active spirit, all light, and always exists one and the same, as it is both beneficial for us to think of God, and as we learn regarding Him from the Scriptures, such feelings and divisions [of operation] cannot fittingly be ascribed to Him. For our tongue, as being carnal, is not sufficient to minister to the rapidity of the human mind, inasmuch as that is of a spiritual nature, for which reason our word is restrained within us, and is not at once expressed as it has been conceived by the mind, but is uttered by successive efforts, just as the tongue is able to serve it.
Source: Adversus haereses (New Advent)