The Four Principles
It was part of his power to know: What you express with words, you have lost power. It is about making talking about these things a sacrificial service; but then the power grows. Nothing is better for the occultist than getting used to keeping silent a lot. Chatting at tea-time and in the evening, voluptuously indulging in talking, causes demons to commit fornication on the astral plane. A clairvoyant can see this, and from a high point of view this is much worse than committing fornication here on the physical plane. Language has become a means of destroying human progress. If you consider what is read merely for the purpose of satisfying oneself - these countless products of modern poets and poetesses (poetians) - you can see what destructive forces are in the world. Today, the greatest progress would be achieved by reading and printing less.
Cite:
GA 265/the_four_principles/p018 · edition English