J. W. Dunne wrote: But there can be no reasonable doubt that the idea of a soul must have first arisen in the mind of primitive man as a result of observation of his dreams. Ignorant as he was, he could have come to no other conclusion but that, in dreams, he left his sleeping body in one universe and went wandering off into another. It is considered that, but for that savage, the idea of such a thing as a soul would never have even occurred to mankind....

Hindu
In the Mandukya Upanishad, part of the Veda scriptures of Indian Hinduism, a dream is one of three states that the soul experiences during its lifetime, the other two states being the waking state and the sleep state. The earliest Upanishads, written before 300 BCE, emphasize two meanings of dreams. The first says that dreams are merely expressions of inner desires. The second is the belief of the soul leaving the body and being guided until awakened. Abrahamic
In Judaism, dreams are considered part of the experience of the world that can be interpreted and from which lessons can be garnered. It is discussed in the Talmud, Tractate Berachot 55–60. The ancient Hebrews connected their dreams heavily with their religion, though the Hebrews were monotheistic and believed that dreams were the voice of one God alone. Hebrews also differentiated between good dreams (from God) and bad dreams (from evil spirits). The Hebrews, like many other ancient cultures, incubated dreams in order to receive a divine revelation.
Dreams can usually be recalled if a person is awakened while dreaming. Women tend to have more frequent dream recall than men. Dreams that are difficult to recall may be characterized by relatively little affect, and factors such as salience, arousal, and interference play a role in dream recall. Often, a dream may be recalled upon viewing or hearing a random trigger or stimulus. The salience hypothesis proposes that dream content that is salient, that is, novel, intense, or unusual, is more easily remembered. There is considerable evidence that vivid, intense, or unusual dream content is more frequently recalled. A dream journal can be used to assist dream recall, for personal interest or psychotherapy purposes. Adults report remembering around two dreams per week, on average. Unless a dream is particularly vivid and if one wakes during or immediately after it, the content of the dream is typically not remembered. Recording or reconstructing dreams may one day assist with dream recall. Using the permitted non-invasive technologies, functional magnetic resonance imaging (fMRI) and electromyography (EMG), researchers have been able to identify basic dream imagery, dream speech activity and dream motor behavior (such as walking and hand movements).In line with the salience hypothesis, there is considerable evidence that people who have more vivid, intense or unusual dreams show better recall. There is evidence that continuity of consciousness is related to recall. Specifically, people who have vivid and unusual experiences during the day tend to have more memorable dream content and hence better dream recall.