On the Astral Plane there are countless subplanes, and divisions thereof, all of which are more or less independent of each other. The distinctions between the planes are altogether the result of differences on the rate of vibrations, and do not represent distances in space. Each sub-plane or division thereof is inhabited by souls exactly fitted to dwell upon it, by reason of their respective degree of spiritual enfoldment. The great law of attraction operates in producing this result, and each soul “feels perfectly at home” on the plane in which it finds itself. The law works with unerring accuracy, and makes no mistakes.
By certain fixed natural laws each soul is restricted to the realms of its own sub-plane or division of the Astral Plane, except that it may, if it desires, visit the planes beneath its own—but it cannot visit those higher than its own. The law of vibrations acts as the astral policemen in these matters. Disembodied souls may thus communicate with and have converse and association with each other, but only by the higher soul visiting the lower, and never the reverse.
The “scenery” and environment of the various sub-planes of the Astral Plane correspond with the ideas and beliefs of the souls occupying them. The Indian may find his “happy hunting ground” much more truly than some people would have us think. The thoughts and ideals of the soul is reflected upon the receptive substance of the Astral Plane, and each soul, in a certain sense, is the creator of its own environment and world—by its thought forms it builds itself a congenial world.
The soul makes progress during its sojourn on the Astral Plane, and prepares itself for a better and happier environment upon rebirth. During that sojourn it assimilates and digests the experiences of its last earth life, and learns the true lessons of such experiences, and these are reflected in the new character which it is forming. Past mistakes are seen, and the true meaning of many puzzling experiences are perceived. The soul thus “takes stock” of itself and is better prepared to meet the conditions of its next earth life.
On the Astral Plane the soul also receives the aid and assistance of some of the great spiritual teachers of the race, whose chosen occupation is to administer to the wants of the pained and suffering souls who are striving to find the way out of their troubles and mistakes. Not only do these teachers administer to the strictly spiritual wants of the souls seeking their help, but in many cases the soul is given the advantage of great assistance in chosen occupations, such as art, science, music, invention, etc., from advanced congenial souls ready and willing to help strugglers on the path. Many an artist, musician, writer, or inventory has come into rebirth greatly benefited and improved by reason of contact with such helpers of the Astral Plane.
Finally, after the longer or short period of sojourn of the soul upon the Astral Plane—the duration of which depends upon the degree of spiritual development of the soul—there comes to it the first dawn of a new state or condition, known to occultists as “the second soul-sleep,” or slumber, in which the soul is prepared for its new birth on earth which is coming to it.
— excerpt from The Secret Doctrine of the Rosicrucians, by Magus Incognito,