I've been wanting to get back into this study for a while.  I felt real opposition at the first couple attempts.  Here is the first chapter from F. C. Jennings.  He is sometimes imaginative beyond prudence, but I have found him very valuable in past studies -- especially Isaiah.

Satan: His Person, Work, Place and Destiny
CHAPTER I.
INTRODUCTORY.

Contents.
The subject both difficult and solemn--The divine inspiration of the
Scriptures must be assumed as forming a standard of truth--What
Science has to say to the subject--What Reason has to say.

The subject on which I desire to write is one of both peculiar difficulty and solemnity. Of difficulty on more accounts than one, but more particularly in view of the false, and, indeed, heathenish ideas that have been bequeathed to us from times of darkness and superstition; and the acceptance of which can only be due to a guilty neglect on our part of the plain teaching of God’s Word. This has indeed been largely modified of late years by many excellent works on this, and closely related subjects; and I have to express my indebtedness to these for the many suggestions they have given, and of which I have availed in the following pages.
But the subject is also one of profound solemnity, and weighty is the responsibility attached to undertaking its elucidation. We are well aware that it is only too customary, even amongst some Christians, to greet even the mention of the name of our dread enemy with a smile; or to turn a witticism with that name as though it really meant nothing; but grant even the possibility of such an existence, and none but fools would treat it with levity.
Grant, again I say, the bare possibility of the existence of such a being of transcendent powers, himself at the head of hosts of others similarly endued; to whom we owe the loss of original innocence and its accompanying happiness; who has overcome man in fair fight, even when not weighted, as now, with a corrupt nature; who is still pledged to withstand the return of every or any individual to God--grant the bare possibility, too, of every Christian being engaged in a conflict of life or death with such an one, and one is compelled to approach the subject--even on the assumption of these possibilities--with such awe, and so to feel the danger of either receiving or communicating any false view of it, as to cry, “Who is sufficient for these things?” Blessed be God, that we are permitted to add “Our sufficiency is of God.”
I am well aware that to assume the simple existence of the Devil will be looked upon as begging the whole question. That this, as well as all other points, must not be taken for granted, but must be proved. And this, I readily admit; only on the other hand, it must also be admitted that something must be mutually accepted as a standard of Truth to which appeal can be made for that proof.
Now, it is not within my purpose to write for those who doubt or question that those writings known as the Scriptures, or the Bible, give us exactly this standard. Were such readers as questioned this to be, at least primarily in view, it would be necessary first to seek to establish the authority of those Scriptures as providing a divine, and therefore perfect standard of truth; and however important a part this may have in Christian ministry in these days, I shall not esteem it to be necessary for those for whom I write. Yet will such a consideration of our subject--basing everything upon the Scriptures--(God giving His gracious blessing) surely result in establishing the authority of those Scriptures the more firmly where it is already held, and where there is even simple honesty and candour, it will at least be seen that they put nothing before us that is not worthy of unreserved acceptance; or that, in the dignity, reasonableness, sobriety with which they deal with this theme, give any ground for considering them other than the very Word of God. Nay, in the marvellous and beauteous light they afford on the unseen spiritual world, its inhabitants, and their connection with the Earth, and which in itself goes far reasonably to account for the contradictions and anomalies that so press upon every thoughtful mind in the things seen, they prove themselves to be as far above all human writings of all ages as the heavens are above the earth-- that is, they are Divine.
Granting this, then, the next step follows as a necessary consequence, that Satan or the Devil is an actual, literal, living personality.
It is quite true that if this were put to the vote of professing Christendom at large, and that vote taken, in accord with the fast-growing democratic principles of our day, as settling or governing things, we should find that the Devil did not exist at all. We have discovered a very easy and very flattering method of disposing of disagreeable subjects. They are entirely dependent on our own will and pleasure; all we have to do is to say “we do not believe in them,” or more effectually, “no one believes in them now”; or perhaps still more unanswerably, “no thoughtful person accepts them” (for we all desire to be considered “thoughtful”) and lo--they are not!
Neither Judgment, nor Hell, nor Satan exist unless we choose to believe in them; and in this convenient, if thoroughly childish method, the mass of professing Christians flatter themselves that, whilst they retain all that is pleasing to them in Revelation, they have got rid of what, after all, may equally prove eternal realities, simply because these realities intrude on, and clash with, the easy-going pleasure-loving spirit of the day. It is surely the part of simple reason to learn if there be not the same clear ground for accepting one set of these as the other. Indeed, if we do accept the Bible as giving us all the light we can possibly have on such mighty facts as Christ, heaven, life, surely it is worse than folly, it is literally suicidal, to deny or ignore it as an authority on themes that are exactly of the same nature, although of a contrasted character; the Devil, hell, judgment; for in so doing, we do really--however much one may wish to avoid such a consequence--shake the very basis of all our brightest hopes.
As far as the Scriptures go, the personality of the Devil is as clearly revealed as the personality of Christ. Indeed, those who deny that of the former, really destroy the latter as a Saviour; for if He were not externally tempted to evil--i. e., if those evil suggestions to make the stone into bread, to obtain the kingdom of the earth by devil-worship, or to cast himself down from the pinnacle of the temple--did not come to Him from some living intelligence (for it is impossible to conceive of such suggestions apart from intelligence) external to Himself, then must they have come from within; and that being the case, He Himself needed a Saviour rather than was one; may God forgive even a statement of a blasphemy we repudiate and abhor with all our heart.
The Devil is then, according to Scripture, an actual, living, reasoning being; and, in some way, the embodiment of evil, as God of good; and who can deny it? “Oh,” it is said, “such a thought even, is not in harmony with, or worthy of, the scientific attainments of our enlightened day.” But what has Science to do with such a question? Science is what is known by human research in the various fields of natural phenomena. It has to do, from its very name and nature, with what is knowable, or capable of recognition in some way, by man’s senses; that is, it is limited to, and has to do with ascertainable facts, ascertainable by man’s capacities, without supernatural assistance. The very denial of there being anything beyond the limit of man’s capacities is really, in the truest sense, unscientific, for it is an intrusion into that which, from its very nature, is beyond that limit, and how can he assume to know anything, either pro or con, of that? For unless man’s powers are infinite (in which case he is indeed God, and with such claimants argument would be thrown away) they must have a limit. If a limit, then he cannot go beyond that limit, either to deny or assert. And to claim capability for knowing what exists, or does not exist there, since this is clearly unknowable, is utterly unscientific.
It would be more strictly “scientific,” that is in accord with human knowledge and its necessary limitations, to say: “I know that since my capacities are not infinite but limited, there must be a sphere outside the limits of those capacities, as to which, from the very nature of the case, I must be dependent on external revelation coming from that sphere, if I attain to any knowledge at all.” That would at least be common sense, and common sense is not very far from true science.
But this being granted, we must also admit that there may be true, and indeed unavoidable deductions drawn from evident facts, as there may also be hypotheses more or less probable based upon them; but a clear distinction must ever be made between the basal facts, and the hypotheses. The former are within the sphere of true science, the latter are outside it, and simply the progeny of a science, falsely so-called, for hypothesis cannot possibly be knowledge; yet, simple truism as this is, it is constantly overlooked. For instance, there are clear similarities, and gradations of these, in the external forms of all creatures; as, for example, there is some external similarity between the body of man and the body of the anthropoid ape; this may be called Science, for it is capable of proof. Evolution is the hypothesis based on this fact, but this is not science, for it remains without proofs, and the voice of protest against its claims to being this, is becoming constantly louder, and its volume is now being swelled even by scientists themselves, amongst whom there is setting in that strange, restless reaction that in itself proves how, admirably selected was that word of Scripture that calls all this kind of thing “science falsely so called.” Nothing is more misnamed than this pseudo-science to which the mass of professing Christians are bowing the knee and receiving as if it were a god. It is. A false god.
Further, it is not without deep significance that ever increasing numbers of scientific men, men with certainly no bias towards faith in the supernatural, quite the reverse, have been, and are being compelled by the utterly inexplicable phenomena of so-called spiritualism, either to predicate some new “force” with regard to whose properties and powers they are in absolute ignorance, or plainly to give that “force” the name of “spirit.” It is true that they will admit of no spirits but those of the dead from among men, but that one need not discuss here. We know another solution to these mysterious manifestations, other spirits quite capable of producing them. The point is that when men like Sir Oliver Lodge, Sir William Crookes, A. R. Wallace, Professor Lombroso, and a host of thoughtful, careful, and, in a sense, sagacious men, who have a world-wide reputation for being “scientific,” are forced, against all preconceived views, constitutional bias, educational training, and temperamental prejudices, to recognize a spiritual sphere, it is not without the greatest significance. Indeed, so far has this gone, that the method hitherto adopted of dismissal of the subject by a kind of superior waive of the hand as being made up entirely of fraud, quite unworthy of being even considered by any one of discernment, is now rather an unconscious confession of superficiality and thoughtlessness, if not of sluggishness and cowardice, than evidence of any sincere or intelligent research, and conviction based upon it.
But it may be further urged, apart altogether from Science, Reason revolts at the assumption of such an existence as the Devil. But this objection at once provokes a counter question: “Whose reason?” It is beyond argument that, even up to the present moment, the reason of myriads of men, amongst whom may be counted many of the keenest human intelligence, and of profoundest human learning, has not revolted, but has unreservedly accepted such an existence as a fact, and as accounting, in a reasonable way, for facts otherwise inexplicable. That the reason of a Milton or of a Newton, or of a Faraday did not revolt against such an assumption is surely quite sufficient to prove that Reason, per se, does not necessarily reject this clearly revealed fact.
To this of course it will be objected that those grand intellects were themselves under the spell of the times in which they lived; even as a Socrates accepted the false gods of heathendom from the same cause. And it would be as reasonable to claim from this that idolatry was as much in harmony with reason as the existence of evil spirits. We fully concur, and admit that reason has never revolted at the recognition of some powers behind the idols, even the very demons of whom our subject is chief. We may say that the reason of a Socrates as of a Faraday accepted the same personality, although the one in heathen darkness and the other in the light of divine revelation, gave that personality differing names and attributes. But up to the present hour multitudes of not the least thoughtful or intelligent of mankind find nothing contrary to reason in such an existence as is so plainly revealed.
For revealed it is, and I shall not therefore esteem it necessary to go further in proving the personality of the Devil; nor would it come within the limits of my present purpose to go into the subject or even consider the striking and interesting correlative theme of demonology. Nor the closely allied one of what is called spiritualism, at least, with any detail.
I shall speak as a Christian believer, who accepts heartily and fully, and after over forty years of daily examination and search, the Bible, as a Divine revelation to men, to others of the same conviction; only seeking to get from that one pure source alone, and by the same goodness that gave it, such light as its author has seen fit to give us on the one single point of Satan, his person, work and destiny; and to sweep away the dust, and cob-webs of mere tradition, or popular folly that have buried this truth, obscured this light, and eventually given us a merely ridiculous parody on this, as on many other subjects, and to show that it is rather this parody that is rejected, and that this rejection does not affect in the slightest degree the truth of Scripture.

End of Chapter One
F. C. Jennings on Satan