Do fallen angels exist
The belief of evil spirits has been almost universal in the world. The exceptions may indeed be said to be only the few who, in more modern times, have supposed this universal opinion to be simply the result of superstition.
The Jews undoubtedly held this faith. It is not disputed that it is taught in their later books, and that in the time of Christ the belief in such spirits was universal. But it has been denied that such views can be traced prior to the time of the Babylonish Captivity. If by this is simply meant that prior to that time the Jews knew not of the fall of angels formerly pure, it is only equivalent to declaring that they knew not in what manner evil angels had come into existence. But if it is meant, as seems to be the case, that they did not know of the existence of evil angels, the position may be easily refuted from the Scriptures. That this is the opinion of these objectors is plain from the fact that they suppose the origin of these ideas was the Persian belief of the two principles of good and evil which they had met with in Chaldea. That faith taught indeed the origin of evil in this world, but not among the spiritual intelligences above. Besides, it attributed the existence of evil to an antagonistic principle to the great good, perhaps equally powerful, yet constantly contending, perhaps finally to be vanquished.
The fact that the existence of these beings is taught at all, either in the Old or the New Testament, would be sufficient to make it an article of our faith. Yet, as this charge has been made, it is best to refer to it, and to show from the Scripture proofs that it is untenable. The truth is that with the exception of Zechariah 3:1, 2 (where the high priest Joshua is standing before the angel of the Lord, and Satan standing at his right hand to resist him), there is no passage in all the post-Babylonish Scriptures by which the doctrine of evil angels could be proved, while there are numerous such passages in the earlier books.
In the book of Job, supposed by some to be the oldest, and sometimes even ascribed to Moses, Satan is represented as presenting himself among the sons of God before the LORD. Job 1:6.
This may be said to be a merely dramatic work, yet scarcely can it be denied that the conception of such beings must have existed prior to a dramatic use of them.
In 1 Chron. 21:1, however, Satan is said to have provoked David to number Israel. In Ps. 109:6 the Psalmist says: “Set thou a wicked man over him, and let an adversary (Satan) stand at his right hand.” The use of the word “devil” also teaches the existence of evil spirits. In Ps. 106:37 the Israelites are said to have sacrificed their sons and daughters unto devils (demons).
Evil angels are also spoken of by the name of “evil spirits.” In Judges 9:23 God is said to have sent an evil spirit between Abimelech and the men of Shechem. In 1 Sam. 16:14 the Spirit of the Lord is said to have departed from Saul, and an evil spirit from the Lord to have troubled him; in ver. 15 Saul’s servants recognize this fact in addressing Saul, and verse 16 propose to send for a skilful player on the harp, through whom he should be made well, and in verse 23 this device is spoken of as successful.
When we turn now to the New Testament, we find the proofs even more abundant. No one questions that this is the apparent language of this part of Scripture, whatever explanations are resorted to for escaping its plain meaning. The passages are not here presented because they will be quoted in connection with other points, and enough of them will then be given to prove this a New Testament doctrine. Including both the singular and plural forms, the word “diabolus” is found in the New Testament about forty times, demon sixty times, Satan twenty-three times, evil spirit eight times, dumb spirit three times, and spirit of divination once.
The commonly received doctrine as to the original state of evil angels, is that they were once pure and holy, such as are now the angels of heaven, though not, as they, confirmed in holiness. This is founded upon the supposition that it is impossible for God to create beings otherwise than free from sin.
The only objection which can be made to this original innocence is suggested in such questions as these: how can a being perfectly holy be led to the commission of sin? how would a being realizing the character and power of the supreme being ever be so unwise as to revolt against it?
But these questions present only metaphysical difficulties which must vanish before actual facts. The existence of such beings is plainly taught; we are told in Scripture that they sinned, 2 Pet. 2:4, and all argument of this kind is merely an argument from our ignorance.
It might be supposed that appeal might be made to the case of Adam; but, while this is true to some extent, this difference must be observed, that there was present with our first parents an evil one to suggest the sin. Yet, even then, the suggestion might have arisen within the mind of either Adam or Eve as the result of desire in any way awakened, which, when fostered, may have become too strong. And, if this be psychologically possible with them, why may it not have been so with Satan and his angels?
It has been because of the difficulties which thus have seemed to perplex this question that on the one hand the very existence of such beings has been questioned; and, on the other, the theory has been advanced that Satan, either as created or uncreated, has always had a sinful nature, and been filled with enmity to God. Both theories are readily dispelled by the fact that the Scriptures speak of their having sinned with manifest allusion to some one particular act of sin.
Boyce, J. P. (2010). Abstract of Systematic Theology (pp. 181–184). Bellingham, WA: Logos Bible Software.