7 But we shall not be wrong if we affirm the same thing also concerning the substance of matter, that God produced it. For we have learned from the Scriptures that God holds the supremacy over all things. But whence or in what way He produced it, neither has Scripture anywhere declared; nor does it become us to conjecture, so as, in accordance with our own opinions, to form endless conjectures concerning God, but we should leave such knowledge in the hands of God Himself.
In like manner, also, we must leave the cause why, while all things were made by God, certain of His creatures sinned and revolted from a state of submission to God, and others, indeed the great majority, persevered, and do still persevere, in [willing] subjection to Him who formed them, and also of what nature those are who sinned, and of what nature those who persevere—[we must, I say, leave the cause of these things] to God and His Word, to whom alone He said, “Sit at my right hand, until I make Your enemies Your footstool.” But as for us, we still dwell upon the earth, and have not yet sat down upon His throne.
For although the Spirit of the Saviour that is in Him “searches all things, even the deep things of God,” yet as to us “there are diversities of gifts, differences of administrations, and diversities of operations;” and we, while upon the earth, as Paul also declares, “know in part, and prophesy in part.” Since, therefore, we know but in part, we ought to leave all sorts of [difficult] questions in the hands of Him who in some measure, [and that only,] bestows grace on us. That eternal fire, [for instance,] is prepared for sinners, both the Lord has plainly declared, and the rest of the Scriptures demonstrate.
And that God foreknew that this would happen, the Scriptures do in like manner demonstrate, since He prepared eternal fire from the beginning for those who were [afterwards] to transgress [His commandments]; but the cause itself of the nature of such transgressors neither has any Scripture informed us, nor has an apostle told us, nor has the Lord taught us. It becomes us, therefore, to leave the knowledge of this matter to God, even as the Lord does of the day and hour [of judgment], and not to rush to such an extreme of danger, that we will leave nothing in the hands of God, even though we have received only a measure of grace [from Him in this world].
But when we investigate points which are above us, and with respect to which we cannot reach satisfaction, [it is absurd] that we should display such an extreme of presumption as to lay open God, and things which are not yet discovered, as if already we had found out, by the vain talk about emissions, God Himself, the Creator of all things, and to assert that He derived His substance from apostasy and ignorance, so as to frame an impious hypothesis in opposition to God.
Source: Adversus haereses (New Advent)