Introduction
 

Question # 154 of "The Spirits' Book":
Q. In what sense should we understand eternal life?
A. "The life of the spirit is everlasting. The life of the body is transitory and fleeting.  When the body dies, the soul re-enters the world of eternal life."

Death, as we call it, is not synonymous to annihilation.  It is merely the passage of the spirit from the material to the spiritual world, upon completion or termination of its material existence.  The process of uniting the spirit with the physical body, from gestation to birth, involves the union of the life-giving, vital principle with the material body to which the spirit to reincarnate will be joined, and remain linked, throughout the extent of its incarnation.  What happens in the process of "death", then, is the withdrawal of this vital principle and the consequential exhaustion of bodily organs. In other words, when the organs are destroyed or too deeply injured, the vital energy is powerless to animate them, and the being dies.

The spirit, then, is freed from the material body that, during the spirit's last life in the material realm, served as a material covering and allowed it to interact in that environment.  Upon return to the spirit world, the only thing the spirit retains from it's incarnate life are its memories.