When, therefore, the number of men had begun to increase, God in His forethought, lest the devil, to whom from the beginning He had given power over the earth, should by his subtilty either corrupt or destroy men, as he had done at first, sent angels for the protection and improvement206 of the human race; and inasmuch as He had given these a free will, He enjoined them above all things not to defile themselves with contamination from the earth, and thus lose the dignity of their heavenly nature.207 He plainly prohibited them from doing that which He knew that they would do, that they might entertain no hope of pardon. Therefore, while they abode among men, that most deceitful ruler208 of the earth, by his very association, gradually enticed them to vices, and polluted them by intercourse with women. Then, not being admitted into heaven on account of the sins into which they had plunged themselves, they fell to the earth. Thus from angels the devil makes them to become his satellites and attendants. But they who were born from these, because they were neither angels nor men, but bearing a kind of mixed209 nature, were not admitted into hell, as their fathers were not into heaven. Thus there came to be two kinds of demons; one of heaven, the other of the earth. The latter are the wicked210 spirits, the authors of all the evils which are done, and the same devil is their prince.Whence Trismegistus calls him the ruler of the demons. But grammarians say that they are called demons, as though doemones,211 that is, skilled and acquainted with matters: for they think that these are gods. They are acquainted, indeed, with many future events, but not all, since it is not permitted them entirely to know the counsel of God; and therefore they are accustomed to accommodate212 their answers to ambiguous results. The poets both know them to be demons, and so describe them.
Hesiod thus speaks:-
"These are the demons according to the will of Zeus, Good, living on the earth, the guardians of mortal men."
And this is said for this purpose, because God had sent them as guardians to the human race; but they themselves also, though they are the destroyers of men, yet wish themselves to appear as their guardians, that they themselves may be worshipped, and God may not be worshipped. The philosophers also discuss the subject of these beings. For Plato attempted even to explain their natures in his "Banquet; "and Socrates said that there was a demon continually about him, who had become attached to him when a boy, by whose will and direction his life was guided. The art also and power of the Magi altogether consists in the influences213 of these; invoked by whom they deceive the sight of men with deceptive illusions,214 so that they do not see those things which exist, and think that they see those things which do not exist. These contaminated and abandoned spirits, as I say, wander over the whole earth, and contrive a solace for their own perdition by the destruction of men. Therefore they fill every place with snares, deceits, frauds, and errors; for they cling to individuals, and occupy whole houses from door to door, and assume to themselves the name of genii; for by this word they translate demons in the Latin language. They consecrate these in their houses, to these they daily pour out215 libations of wine, and worship the wise demons as gods of the earth, and as averters of those evils which they themselves cause and impose. And these, since spirits are without substance216 and not to be grasped, insinuate themselves into the bodies of men; and secretly working in their inward parts, they corrupt the health, hasten diseases, terrify their souls with dreams, harass their minds with phrenzies, that by these evils they may compel men to have recourse to their aid.
Chapter xvi.-That Demons Have No Power Over Those Who are Established in the Faith.
And the nature of all these deceits217 is obscure to those who are without the truth. For they think that those demons profit them when they cease to injure, whereas they have no power except to injure.218 Some one may perchance say that they are therefore to be worshipped, that they may not injure, since they have the power to injure. They do indeed injure, but those only by whom they are feared, whom the powerful and lofty hand of God does not protect, who are uninitiated in the mystery219 of truth. But they fear the righteous,220 that is, the worshippers of God, adjured by whose name they depart221 from the bodies of the possessed: for, being lashed by their words as though by scourges, they not only confess themselves to be demons, but even utter their own names-those which are adored in the temples-which they generally do in the presence of their own worshippers; not, it is plain, to the disgrace of religion, but222 to the disgrace of their own honour, because they cannot speak falsely to God, by whom they are adjured, nor to the righteous, by whose voice they are tortured. Therefore ofttimes having uttered thegreatest howlings, they cry out that they are beaten, and are on fire, and that they are just on the point of coming forth: so much power has the knowledge of God, and righteousness! Whom, therefore, can they injure, except those whom they have in their own power? In short, Hermes affirms that those who have known God are not only safe from the attacks of demons, but that they are not even bound by fate. "The only protection," he says, "is piety, for over a pious man neither evil demon nor fate has any power: for God rescues the pious man from all evil; for the one and only good thing among men is piety." And what piety is, he testifies in another place, in these words: "For piety is the knowledge of God." Asclepius also, his disciple, more fully expressed the same sentiment in that finished discourse which he wrote to the king. Each of them, in truth, affirms that the demons are the enemies and harassers of men, and on this account Trismegistus calls them wicked angels; so far was he from being ignorant that from heavenly beings they were corrupted, and began to be earthly.
God, therefore, the contriver and founder of all things, as we have said in the second hook, before He commenced this excellent work of the world, begat a pure and incorruptible Spirit, whom He called His Son. And although He had afterwards created by Himself innumerable other beings, whom we call angels, this first-begotten, however, was the only one whom He considered worthy of being called by the divine name, as being powerful in His Father's excellence and majesty. But that there is a Son of the Most High God, who is possessed of the greatest power, is shown not only by the unanimous utterances of the prophets, but also by the declaration of Trismegistus and the predictions of the Sibyls. Hermes, in the book which is entitled The Perfect Word, made use of these words: "The Lord and Creator of all things, whom we have thought right to call God, since He made the second God visible and sensible. But I use the term sensible, not because He Himself perceives (for the question is not whether He Himself perceives), but because He leads25 to perception and to intelligence. Since, therefore, He made Him first, and alone, and one only, He appeared to Him beautiful, and most full of all good things; and He hallowed Him, and altogether loved Him as His own Son." The Erythraean Sibyl, in the beginning of her poem, which she commenced with the Supreme God, proclaims the Son of God as the leader and commander of all, in these verses:
"The nourisher and creator of all things, who placed the sweet breath in all, and made God the leader of all."
And again, at the end of the same poem:-
"But whom God gave for faithful men to honour."
And another Sibyl enjoins that He ought to be known:-
"Know Him as your God, who is the Son of God."
Assuredly He is the very Son of God, who by that most wise King Solomon, full of divine inspiration, spake these things which we have added:26 "God founded27 me in the beginning of His ways, in His work before the ages. He set me up in the beginning, before He made the earth, and before He established the depths, before the fountains of waters came forth: the Lord begat me before all the hills; He made the regions, and the uninhabitable28 boundaries under the heaven. When He prepared the heaven, I was by Him: and when He separated His own seat, when He made the strong clouds above the winds, and when He strengthened the mountains, and placed them under heaven; when He laid the strong foundations of the earth, I was with Him arranging all things. I was He in whom He delighted: I was daily delighted, when He rejoiced, the world being completed." But on this account Trismegistus spoke of Him as "the artificer of God," and the Sibyl calls Him "Counsellor," because He is endowed by God the Father with such wisdom and strength, that God employed both His wisdom and hands in the creation of the world.
But the Greeks speak of Him as the Logos,60 more befittingly than we do as the word, or speech: for Logos signifies both speech and reason, inasmuch as He is both the voice and the wisdom of God. And of this divine speech not even the philosophers were ignorant, since Zeno represents the Logos as the arranger of the established order of things, and the framer of the universe: whom also He calls Fate, and the necessity of things, and God, and the soul of Jupiter, in accordance with the custom, indeed, by which they are wont to regard Jupiter as God. But the words are no obstacle, since the sentiment is in agreement with the truth. For it is the spirit of God which he named the soul of Jupiter. For Trismegistus, who by some means or other searched into almost all truth, often described the excellence and majesty of the word, as the instance before mentioned declares, in which he acknowledges that there is an ineffable and sacred speech, the relation of which exceeds the measure of man's ability. I have spoken briefly, as I have been able, concerning the first nativity. Now I must more fully discuss the second, since this is the subject most controverted, that we may hold forth the light of understanding to those who desire to know the truth.
<a href="http://ls.poly.edu/~jbain/mms/texts/mmslanctantius.htm">from The Divine Institutes</a>