Reincarnation (“Gilgul Neshamot”, “גלגול נשמות” in Hebrew) describes the concept that after the death of the body, the soul or spirit of the human comes back to life in a body of a new human or in some other beliefs in an already living human being. Some beliefs even talk about reincarnation as an animal or even a plant.
According to the Kabbalah the desire of the soul is to remain always in a state of total awareness without any dependency on the physical body.
The reincarnation main purpose by the Kabbalah is to bring the reform and improvement of the soul (“Tikun, “תיקון” “in Hebrew) from past experiences. It is commonly believed that once the soul has developed fully it doesn’t have any more desire to reincarnate.
There are several explanations about why the reincarnation occurs. One explanation for reincarnation by the Kabbalah is that reincarnation is a form of punishment and that the soul must be cleansed in order for it to be elevated to the Garden of Eden. The Arizal wrote that until all of the 613 Mitzvot are fulfilled each soul must be reincarnated repeatedly.Another explanation is when a man dies and he doesn’t have any male descendants. This is an important religious issue since it concerns one of the most important mitzvahs (to procreate). In this case the soul of the man reincarnate so he could continue the creation (בריאה) and leave a part from his soul in the world after he dies.