Jason,

I must confess that, because of your recent posts, I laughed when I first read this post.
But you may be sincere.

"Demonic oppression" is a new term. I'm not clear on what is meant by it.

In any case, the Philokalia may be helpful to you. Some texts can be found online.
Examples from various volumes of the Philokalia:

Pray that God may give you grace to see and understand all things clearly, so that you can discriminate correctly between good and evil. It is written by Apostle Paul that "strong meat belongeth to them that are of full age" (Hebrews 5:14). These are men, who by long and diligent work have their senses and intentions trained to discern both good and evil, who have become sons of the kingdom and are enrolled for Divine sonship. God has given them wisdom and good judgement in all their works, so that neither man nor devil can seduce them.
You must know that the enemy tempts the faithful under the guise of good and succeeds in seducing many because they have neither wisdom nor good judgment. Therefore when Apostle Paul had learned the riches of understanding, which are destined for the faithful, and whose greatness has no bounds, he wrote to the Ephesians, "That the God of our Lord Jesus Christ, the Father of glory, may give unto you the spirit of wisdom and revelation in the knowledge of him; the eyes of your understanding being enlightened; that ye may know what is the hope of his calling, and what the riches of the glory of his inheritance in the saints (Ephesians 1: 17-18). He wrote this from his exceeding great love for them, knowing that if they attain it they will find hardship in nothing, no fear will touch them; but the joy of the Lord will comfort them day and night and their labors will be sweet for them at all times.

Many of the monks and virgins living in communities do not attain to this measure. And you, if you wish to attain to this measure, in which is the height of perfection, should withdraw from all those who while they bear such names, that is monkhood and virginity, yet lack this clear vision and good judgment. For, if you become connected with them, they will not let you make progress, and may even cool your ardor, because they themselves have no ardor but only coldness, since they follow their own desires. So, if they come to you and begin worldly conversations, according to their own desires, do not consent to it. For Apostle Paul writes, "Quench not the Spirit. Despise not prophesyings" (I Thessalonians 5: 19-20).
St Anthony the Great, "Early Fathers From the Philokalia," by E. Kadloubovsky and G.E.H. Palmer, (London: Faber and Faber, 1954), pp. 46-51


"What is True Discrimination?"
-- St. Peter of Damaskos

TRUE DISCRIMINATION

If by the grace of God you have received the gift of discrimination, you should in great humility do everything you can to guard it, so that you do nothing without it. Otherwise you will bring on yourself greater chastisement by sinning knowingly because of your negligence. If you have not received
this gift you should not think, say, or do anything without consulting others about it, and without a basis of firm faith and pure prayer. Without such faith and such prayer you will never truly achieve discrimination.

NO DISCRIMINATION WITHOUT HUMILITY

Discrimination is born of humility. On its possessor it confers spiritual insight, as both Moses and St. John Climacus say: such a man foresees the hidden designs of the enemy and foils them before they are put into operation. It is as David states: “And my eyes looked down upon my enemies” (Psalms 54:7).
Discrimination is characterized by an unerring recognition of what is good and what is not, and the knowledge of the Will of God in all that one does. Spiritual insight is characterized, first, by awareness of one’s own failings before they issue in outward actions, as well as of the stealthy tricks of the demons; and, second, by the knowledge of the mysteries hidden in the divine Scriptures and in sensible creation.

As has been already explained, humility, the mother of discrimination and spiritual insight, likewise has its own characteristic by which it is known. The humble person must possess every virtue and yet truly think himself the greatest of debtors and inferior to everything else in creation, even though
he seems to lead a life like that of the angels. For even a true angel possessing so many virtues and so much wisdom cannot conform to the Creator’s Will unless he also possesses humility. What, then, can a person who thinks that he is an angel say for himself if he lacks humility, source of all present and future blessings, begetter of that discrimination which illumines the ends of the earth and without which all things are obscure?

DISCRIMINATION IS LIGHT

Discrimination is not only called light; it truly is light. We need this light before we say or do anything. When it is present we are able to view everything else with wonder. We can marvel at how God, on the first and greatest of days, began by creating light, so that what was subsequently created might not be
invisible and as if it did not exist, as St. John of Damaskos says. Let it be said again: discrimination is light; and the spiritual insight it generates is more necessary than all other gifts. For what is more necessary than to perceive the wiles of the demons and with the help of God’s grace to protect one’s soul? Other things most necessary to us include, according to St. Isaac, purity of conscience; and, according to the apostle, the sanctification of the body (Romans 12:1; I Corinthians 6:19-20) without which “no one will see the Lord” (Hebrews 12:14).
from G. E. H. Palmer, Philip Sherrard, and Bishop Kallistos Ware, "The Philokalia: vol. III," (London: Faber and Faber, 1984), pp. 158 - 159


"The Signs of Grace and Delusion"
-- St. Gregory of Sinai

ON THE SIGNS OF GRACE AND DELUSION, WRITTEN FOR THE CONFESSOR LONGINOS: TEN TEXTS

1. As the great teacher St. John Chrysostom states, we should be in a position to say that we need no help from the Scriptures, no assistance from other people, but are instructed by God; for "all will be taught by God" (Isaiah 54:13, John 6:45), in such a way that we learn from Him and through Him what we ought to know. And this applies not only to those of us who are monks but to each and every one of the faithful: we are all of us called to carry the law of the Spirit written on the tablets of our hearts (II Corinthians 3:3), and to attain like the Cherubim the supreme privilege of conversing through pure prayer in the heart directly with Jesus. But because we are infants at the time of our renewal through baptism we do not understand the grace and the new life conferred upon us. Unaware of the surpassing grandeur of the honor and glory in which we share, we fail to realize that we ought to grow in soul and spirit through the keeping of the commandments and so perceive noetically what we have received. On account of this most of us fall through indifference and servitude to the passions into a state of benighted obduracy. We do not know whether God exists, or who we are, or what we have become, although through baptism we have been made sons of God, sons of light, and children and members of Christ. If we are baptized when grown up, we feel that we have been baptized only in water and not by the Spirit. And even though we have been renewed in the Spirit, we believe only in a formal, lifeless and ineffectual sense, and we say we are full of doubts.

Hence because we are in fact non-spiritual we live and behave in a non-spiritual manner. Should we repent, we understand and practice the commandments only in a bodily way and not spiritually. And if after many labors a revelation of grace is in God's compassion granted to us, we take it for a delusion. Or if we hear from others how grace acts, we are persuaded by our envy to regard that also as a delusion. Thus we remain corpses until death, failing to live in Christ and to be inspired by Him. According to Scripture, even that which we possess will be taken away from us at the time of our death or our judgment because of our lack of faith and our despair (Matthew 25:29). We do not understand that the children must be like the father, that is to say, we are to be made gods by God and spiritual by the Holy Spirit; for "that which is born of the Spirit is spirit" (John 3:6). But we are unregenerate, even though we have become members of the faith and heavenly, and so the Spirit of God does not dwell within us (Genesis 6:3). Because of this the Lord has handed us over to strange afflictions and captivity, and slaughter flourishes, perhaps because He wishes to correct evil, or cut it off, or heal it by more powerful remedies.

2. With the help of God, then, who inspires those who declare good tidings (Psalms 68:11), we must first examine how one finds Christ or, rather, how one is found by Him, since we already possess and have received Him through baptism in the Spirit: as St. Paul says, "Do you not realize that Jesus Christ dwells within you?" (II Corinthians 13:5). Then we must ask how to advance or, simply, how to retain what we have discovered. The best and shortest course is for us to give a brief summary of the whole spiritual journey from start to finish, long though it is. Many, indeed, have been so exhausted by their efforts to discover what they were looking for that, on finding the starting-point, they have remained content with this, and have not tried to advance further. Encountering obstacles and turning aside unawares from the true path, they think that they are on the right track when actually they are veering profitlessly off course. Others, on reaching the halfway point of illumination, have then grown slack, wilting before reaching the end; or they have reverted through their slipshod way of life, and have become beginners again. Yet others, on the point of attaining perfection, have grown inattentive and self-conceited, relapsing to the state of those in the middle way or even of beginners. Beginners, those in the middle way and the perfect have each their distinctive characteristic: for the first it is activity, for the second illumination, for the third purification and resurrection of the soul.

ON HOW TO DISCOVER THE ENERGY OF THE HOLY SPIRIT

3. The energy of the Holy Spirit, which we have already mystically received in baptism, is realized in two ways. First - - to generalize -- this gift is revealed, as St. Mark tells us, through arduous and protracted practice of the commandments: to the degree to which we effectively practice the commandments its radiance in increasingly manifested in us. Secondly, it is manifested to those under spiritual guidance through the continuous invocation of the Lord Jesus, repeated with conscious awareness, that is, through mindfulness of God. In the first way, it is revealed more slowly, in the second more rapidly, if one diligently and persistently learns how to dig the ground and locate the gold. Thus if we want to realize and know the truth and not to be led astray, let us seek to possess only the heart- engrafted energy in a way that is totally without shape or form, not trying to contemplate in our imagination what we take to be the figure or similitude of things holy or to see any colors or lights. For in the nature of things the spirit of delusion deceives the intellect through such spurious fantasies, especially at the early stages, in those who are still inexperienced. On the contrary, let our aim be to make the energy of prayer alone active in our hearts, for it brings warmth and joy to the intellect, and sets the heart alight with an ineffable love for God and man. It is on account of this that humility and contrition flow richly from prayer. For prayer in beginners is the unceasing noetic activity of the Holy Spirit. To start with it rises like a fire of joy from the heart; in the end it is like light made fragrant by divine energy.

4. There are several signs that the energy of the Holy Spirit is beginning to be active in those who genuinely aspire for this to happen and who are not just putting God to the test -- for, according to the Wisdom of Solomon, "It is found by those who do not put it to the test, and manifests itself to those who do not distrust it" (Wisdom 1:2). In some it appears as awe arising in the heart, in others as a tremendous sense of jubilation, in others as joy, in others as joy mingled with awe, or as tremulousness mingled with joy, and sometimes it manifests itself as tears and awe. For the soul is joyous at God's visitation and mercy, but at the same time is in awe and trepidation at His presence because it is guilty of so many sins. Again, in some the soul at the outset experiences an unutterable sense of contrition and an indescribable pain, like the woman in Scripture who labors to give birth (Revelation 12:2). For the living and active Logos -- that is to say, Jesus -- penetrates, as the apostle says, to the point at which soul separates from body, joints from marrow (Hebrews 4:12), so as to expel by force every trace of passion from both soul and body. In others it is manifest as an unconquerable love and peace, shown towards all, or as a joyousness that the fathers have often called exultation -- a spiritual force and an impulsion of the living heart that is also described as a vibration and sighing of the Spirit who makes wordless intercession for us to God (Romans 8:26). Isaiah has also called this the "waves" of God's righteousness (Isaiah 48:18), while the great Ephrem calls it "spurring." The Lord Himself describes it as "a spring of water welling up for eternal life" (John 4:14) -- He refers to the Spirit as water -- a source that leaps up in the heart and erupts through the ebullience of its power.

5. You should know that there are two kinds of exultation or joyousness: the calm variety (called a vibration or sighing or intercession of the Spirit), and the great exultation of the heart -- a leap, bound or jump, the soaring flight of the living heart towards the sphere of the divine. For when the soul has been raised on the wings of divine love by the Holy Spirit and has been freed from the bonds of the passions, it strives to fly to that higher realm even before death, seeking to separate itself from its burden. This is also known as a stirring of the spirit -- that is to say, an eruption or impulsion -- as in the text, "Jesus was stirred in spirit and, deeply moved, He said, 'Where have you laid him?'" (John 11:34). David the Psalmist indicates the difference between the greater and the lesser exultation when he declares that the mountains leap like rams and the little hills like lambs (Psalms 114:6). He is referring of course to those who are perfect and to beginners, for physical mountains and hills, lacking animal life, do not actually leap about.

6. Divine awe has nothing to do with trepidation -- by which I mean, not the tremulousness induced by joy, but the trepidation induced by wrath or chastisement or the feeling of desertion by God. On the contrary, divine awe is accompanied by a tremulous sense of jubilation arising from the prayer of fire that we offer when filled with awe. This awe is not fear provoked by wrath or punishment, but it is inspired by wisdom, and is also described as "the beginning of wisdom "(Psalms 111:10). Awe may be divided into three kinds, even though the fathers speak only of two: the awe of beginners, that of the perfect, and that provoked by wrath, which should properly be called trepidation, agitation or contrition.

7. There are several kinds of trembling. That of wrath is one, that of joy is another, and that of the soul's incensive power, when the heart's blood is over-heated, is another, that of old age is another, that of sin or delusion is another, and that of the curse which was laid on the human race because of Cain is another (Genesis 4:11-15). In the early stages of spiritual warfare, however, it sometimes but not always happens that the trembling induced by joy and that induced by sin contend with one another. The first is the tremulous sense of jubilation, when grace refreshes the soul with great joyfulness accompanied by tears; the second is characterized by a disordered fervor, stupor and obduracy that consume the soul, inflame the sexual organs, and impel one to assent through the imagination to erotic physical obscenities.

ON THE DIFFERENT KINDS OF ENERGY

8. In every beginner two forms of energy are at work, each affecting the heart in a distinct way. The first comes from grace, the second from delusion. St. Mark the Ascetic corroborates this when he says that there is a spiritual energy and a satanic energy, and that the beginner cannot distinguish between them. These energies in their turn generate three kinds of fervor, the first prompted by grace, the second by delusion or sin, and the third by an excess of blood. This last relates to what St. Thalassios the Libyan calls the body's temperament, the balance and concord of which can be achieved by appropriate self- control.

ON DIVINE ENERGY

9. The energy of grace is the power of spiritual fire that fills the heart with joy and gladness, stabilizes, warms and purifies the soul, temporarily stills our provocative thoughts, and for a time suspends the body's impulsions. The signs and fruits that testify to its authenticity are tears, contrition, humility, self-control, silence, patience, self-effacement and similar qualities, all of which constitute undeniable evidence of its presence.

ON DELUSION

10. The energy of delusion is the passion for sin, inflaming the soul with thoughts of sensual pleasure and arousing phrenetic desire in the body for intercourse with other bodies. According to St. Diadochos it is entirely amorphous and disordered, including a mindless joy, presumption and confusion, accompanied by a mood of ill-defined sterile levity, and fomenting above all the soul's apppetitive power with its sensuality. It nourishes itself on pleasure, aided and abetted by the insatiable belly; for through the belly it not only impregnates and enkindles our whole bodily temperament but also acts upon and inflames the soul, drawing it to itself so that little by little the disposition to self-indulgence expels all grace from the person thus possessed.

from G. E. H. Palmer, Philip Sherrard, and Bishop Kallistos Ware (eds.), "The Philokalia: Volume Four," (London: Faber and Faber, 1995), pp. 257 - 262.


"Texts on Discrimination in respect of Passions and Thoughts" written by Evagrios the Solitary:
Of the demons opposing us in the practice of the ascetic life, there are three groups who fight in the front line: those entrusted with the appetites of gluttony, those who suggest avaricious thoughts, and those who incite us to seek the esteem of men. All the other demons follow behind and in their turn attack those already wounded by the first three groups. For one does not fall into the power of the demon of unchastity, unless one has first fallen because of gluttony; nor is one's anger aroused unless one is fighting for food or material possessions or the esteem of men. And one does not escape the demon of dejection, unless one no longer experiences suffering when deprived of these things. Nor will one escape pride, the first offspring of the devil, unless one has banished avarice, the root of all evil, since poverty makes a man humble, according to Solomon (Prov. 10:4 LXX). In short, no one can fall into the power of any demon, unless he has been wounded by those of the front line. That is why the devil suggested these three thoughts to the Saviour: first he exhorted Him to turn stones into bread; then he promised Him the whole world, if Christ would fall down and worship him; and thirdly he said that, if our Lord would listen to him, He would be glorified and suffer nothing in falling from the pinnacle of the temple. But our Lord, having shown Himself superior to these temptations, commanded the devil to 'get behind Him'. In this way He teaches us that it is not possible to drive away the devil, unless we scornfully reject these three thoughts. (Matt. 4-1-10)
books.google.com/books

<Does anyone have a good online resource distinguishing the two and listing the usual causes? >

You can find many lists on the internet and most have some contentious line items. I don't think you can reduce it to a check list, but essentially a demon possesed person is lacking in control of their own behavior, while a demon oppressed person has bad things happen to them. Suffer from addictions, depression, ect. It is difficult to address demonic possession in this modern age as many are convinced of the medical sciences and the existences of mental illness. Mental illness does exist, but it is just the physical manifestation of demonic possession and oppression. the medical profession in treating mental illness treats the symptoms but exorcism treats the true illness and can offer a real cure, while the medical profession can only offer life long treatment..

The term is not new at all. People working the deliverance quarters have been using it for many years.



The best one I could find so far was this,
www.eternaldestiny.com/DDemons.html


It's got a couple of noticeable errors in it, but I can't find a better one out here yet, and I need this thread to have something agreed upon to fall back on as I pour out a front line battle of heart in a soon to appear thread.

Not exactly what you are asking for, but M. Scott Peck's book "People of the Lie" discusses the nature of human evil. Some of his insights are very interesting and thought-provoking. There is a section on demonic possession that you may find helpful. Peck is a psychiatrist, so he takes a scientific approach to religion and spirituality. I've read several of his books, and while the man was by no means perfect I think he had a lot of valuable things to say.