Reply Obj. 3: Brute beasts have a natural inclination in their sensitive nature towards certain particular goods, with which certain evils are connected; thus the fox in seeking its food has a natural inclination to do so with a certain skill coupled with deceit. Wherefore it is not evil in the fox to be sly, since it is natural to him; as it is not evil in the dog to be fierce, as Dionysius observes (De Div. Nom. iv). _______________________
FIFTH ARTICLE [I, Q. 63, Art. 5]
Whether the Devil Was Wicked by the Fault of His Own Will in the
First Instant of His Creation?
Objection 1: It would seem that the devil was wicked by the fault of his own will in the first instant of his creation. For it is said of the devil (John 8:44): "He was a murderer from the beginning."
Obj. 2: Further, according to Augustine (Gen. ad lit. i, 15), the lack of form in the creature did not precede its formation in order of time, but merely in order of nature. Now according to him (Gen. ad lit. ii, 8), the "heaven," which is said to have been created in the beginning, signifies the angelic nature while as yet not fully formed: and when it is said that God said: "Be light made: and light was made," we are to understand the full formation of the angel by turning to the Word. Consequently, the nature of the angel was created, and light was made, in the one instant. But at the same moment that light was made, it was made distinct from "darkness," whereby the angels who sinned are denoted. Therefore in the first instant of their creation some of the angels were made blessed, and some sinned.
Obj. 3: Further, sin is opposed to merit. But some intellectual nature can merit in the first instant of its creation; as the soul of Christ, or also the good angels. Therefore the demons likewise could sin in the first instant of their creation.
Obj. 4: Further, the angelic nature is more powerful than the corporeal nature. But a corporeal thing begins to have its operation in the first instant of its creation; as fire begins to move upwards in the first instant it is produced. Therefore the angel could also have his operation in the first instant of his creation. Now this operation was either ordinate or inordinate. If ordinate, then, since he had grace, he thereby merited beatitude. But with the angels the reward follows immediately upon merit; as was said above (Q. 62, A. 5). Consequently they would have become blessed at once; and so would never have sinned, which is false. It remains, then, that they sinned by inordinate action in their first instant.
On the contrary, It is written (Gen. 1:31): "God saw all the things that He had made, and they were very good." But among them were also the demons. Therefore the demons were at some time good.
I answer that, Some have maintained that the demons were wicked straightway in the first instant of their creation; not by their nature, but by the sin of their own will; because, as soon as he was made, the devil refused righteousness. To this opinion, as Augustine says (De Civ. Dei xi, 13), if anyone subscribes, he does not agree with those Manichean heretics who say that the devil's nature is evil of itself. Since this opinion, however, is in contradiction with the authority of Scripture—for it is said of the devil under the figure of the prince of Babylon (Isa. 14:12): "How art thou fallen . . . O Lucifer, who didst rise in the morning!" and it is said to the devil in the person of the King of Tyre (Ezech. 28:13): "Thou wast in the pleasures of the paradise of God,"—consequently, this opinion was reasonably rejected by the masters as erroneous.
Hence others have said that the angels, in the first instant of their creation, could have sinned, but did not. Yet this view also is repudiated by some, because, when two operations follow one upon the other, it seems impossible for each operation to terminate in the one instant. Now it is clear that the angel's sin was an act subsequent to his creation. But the term of the creative act is the angel's very being, while the term of the sinful act is the being wicked. It seems, then, an impossibility for the angel to have been wicked in the first instant of his existence.