The Dark Brotherhood
September 25, 1919
Today I seek to speak to you on The powers of the Dark Brotherhood. Certain laws that govern their actions,  certain methods employed by them in work need to be realized and certain methods of protection apprehended and utilized. As before I have told you the danger is as yet inappreciable to the majority, but more and more as time elapses shall we find it necessary to teach you, the physical plane workers, how to shield and guard yourselves from attack.
The Dark Brothers are – remember this always – brothers, erring and misguided yet still sons of the one Father though straying far, very far, into the land of distances. The way back for them will be long, but the mercy of evolution inevitably forces them back along the path of return in cycles far ahead. Anyone who over-exalts the concrete mind and permits it continuously to shut out the higher, is in danger of straying on the left-hand path. Many so stray… but come back, and then in the future avoid like errors in the same way as a child once burnt avoids the fire. It is the man who persists in spite of warning and of pain who eventually becomes a brother of darkness. Mightily fights the Ego at first to prevent the Personality so developing, but the deficiencies of the causal body (for forget not that our vices are but our virtues misused) result in a lop-sided causal body, over-developed in some direction and full of great gulfs and gaps where virtues should be.
The dark brother recognizes no unity with his species, only seeing in them people to be exploited for the furtherance of his own ends. This then, on a small scale, is the mark of those who are being used by them wittingly or unwittingly. They respect no person, they regard all men as fair prey, they use everyone to get their own way enforced, and by fair means or foul they seek to break down all opposition and for the personal self acquire that which they desire. 
The dark brother considers not what suffering he may cause; he cares not what agony of mind he brings upon an opponent; he persists in his intention and desists not from the hurt of any man, woman or child, provided that in the process his own ends are furthered. Expect absolutely no mercy from those opposing the Brotherhood of Light.
On the physical plane and on the emotional plane, the dark brother has more power than the Brother of the Light, – not more power per se but more apparent power, because the White Brothers choose not to exert Their power on those two planes, as do the Dark Brothers. They could exert Their authority but They choose to refrain, working with the powers of evolution and not of involution. The elemental forces to be found on these two planes are manipulated by two factors.
- The inherent forces of evolution that direct all on to eventual perfection. The White Adepts cooperate in this.
- The Dark Brothers who occasionally employ these elemental forces to wreak their will and vengeance on all opponents. Under their control work sometimes the elementals of the earth plane, the gnomes and the elemental essence as found in evil form, some of the brownies, and the fairy folk of colors brown, gray and somber-hued. They cannot control the devas of high development, nor the fairies of colors blue, green and yellow, though a few of the red fairies can be made to work under their direction. The water elementals (though riot the sprites or sylphs) move on occasion to their assistance, and in the control of these forces of involution they at times damage the furtherance of our work. 
Oft too the Dark Brother masquerades as an agent of the light, oft he poses as a messenger of the gods, but for your assurance I would say that he who acts under the guidance of the Ego will have clear vision, and will escape deception.
At this time their power is oft-times mighty. Why? Because so much exists as yet in the Personalities of all men that respond to their vibration, and so it is easy for them to affect the bodies of men. So few of the races, comparatively speaking, have as yet built in the higher vibration that responds to the keynote of the Brotherhood of Light, who move practically entirely on the two highest levels (or the atomic and subatomic subplanes) of the mental, emotional and physical planes. When moving on these subplanes the attacks of elementals on lower planes may be felt but effect no harm, hence the necessity of pure living and controlled pure emotions and elevated thought.
You will notice that I said that the power of the Dark Brotherhood is dominant apparently on the physical and emotional planes. Not so is it on the mental, which is the plane on which the Brothers of the Light work. Mighty dark magicians may be located on the lower mental levels, but on the higher, the White Lodge dominates, the three higher subplanes being the levels that They beg the evolving sons of men to seek; it is Their region, to which all must strive and aspire. The Dark Brother impresses his will on human beings (if analogous vibration exists) and on the elemental kingdoms of involution. The Brothers of Light plead as pleaded the Man of Sorrows for an erring humanity to rise upward to the light. The Dark Brother retards progress and shapes all to his own ends; the Brother of Light bends every effort to the hastening  of evolution and – foregoing all that might be His as the price of achievement – stays amid the fogs, the strife, the evil and the hatred of the period if, in so doing, He may by all means aid some, and (lifting them up out of the darkness of earth) set their feet upon the Mount, and enable them to surmount the Cross.
And now what methods may be employed to safeguard the worker in the field of the world? What can be done to ensure his safety in the present strife and in the greater strife of the coming centuries?
- A realization that purity of all the vehicles is the prime essential. If a Dark Brother gains control over any man it but shows that that man has in his life some weak spot. The door whereby entrance is effected must be opened by the man himself; the opening whereby malignant force can be poured in must be caused by the occupant of the vehicles. Therefore the need of scrupulous cleanliness of the physical body, of clean steady emotion permitted in the emotional body, and of purity of thought in the mental body. When this is so, coordination will be present in the lower vehicles and the indwelling Thinker himself permits no entrance.
- The elimination of all fear. The forces of evolution vibrate more rapidly than those of involution and in this fact lies a recognizable security. Fear causes weakness; weakness causes a disintegration; the weak spot breaks and a gap appears, and through that gap evil force may enter. The factor of entrance is the fear of the man himself, who opens thus the door.
- A standing firm and unmoved, no matter what occurs. Your feet may be bathed in the mud of earth, but your head may be bathed in the sunshine of the higher regions. Recognition of the filth of earth involves not contamination. 
- A recognition of the use of common sense and the application of this common sense to the matter in hand. Sleep much and, in sleeping, learn to render the body positive; keep busy on the emotional plane and achieve the inner calm. Do naught to overtire the body physical, and play whenever possible. In hours of relaxation comes the adjustment that obviates later tension. 
Letters on Occult Meditation – Letter V – Dangers to be avoided in Meditation
Alice Bailey & Djwhal Khul