The Spirits' Book
Book Two - The Spirit World
Chapter VIII - Emancipation of the Soul
Sleep and Dreams
403. Why do we not always remember our dreams?
“Sleep is only rest for the body, and the spirit always remains active. The spirit is partially free while sleeping, and communicates with loved ones, in both this world and other worlds. As the body is heavy and material, it is difficult for it to retain possession of the impressions received by the spirit during sleep, because those impressions were not received through the physical organs.”