“During life, a spirit is held to the body by his semi-material envelope, or perispirit. Death is the destruction of the body only, but not of this second envelope, which separates itself from the body when the play of organic life ceases in the latter. Observation shows us that the separation of the perispirit from the body is not suddenly completed at the moment of death, but is only effected gradually, and more or less slowly in different individuals. In some cases it is effected so quickly that the perispirit is entirely separated from the body within a few hours of the death of the latter but in other cases, and especially in the case of those whose life has been grossly material and sensual, this deliverance is much less rapid, and sometimes takes days, weeks, and even months, for its accomplishment. This delay does not imply the slightest persistence of vitality in the body, nor any possibility of its return to life, but is simply the result of a certain affinity between the body and the spirit which affinity is always more or less tenacious in proportion to the preponderance of materiality in the affections of the spirit during his earthly life.”

Source: The Spirits' Book, p. 116.