-Certain rectifications can only be done in the physical world because it is confined to the dimensions of space.
-When a person dies it is not over, his soul must be rectified.
-After he earns the right he can sometimes cloth himself in the body of a person or creature under going an experience which is his rectification.
-Meaning he goes on as a rider not affecting his host, leaving after the rectification is accomplished.
-Example, if a person committed an act of murder while alive he might have to cloth himself into another person as he is being killed.
-The host deserves to be killed either way for his personal sins. The soul feels all that is experienced by the host, but not necessarily effecting him.
-This explains certain cases of gilgulim (reincarnations).