Reincarnation: The Transmigration of a Jewish Idea
Though some Jewish thinkers vigorously rejected the notion of reincarnation, kabbalists embraced it enthusiastically.
The reincarnation of souls into other people or animals--known as gilgul hanefesh (lit. the rolling of the soul) in Hebrew--is an outgrowth of the idea of the soul's immortality. It has seized the imagination of many Jews and remains a popular literary subject. Numerous stories of demonic possession and exorcism by wonder rabbis are based on the idea of lonely souls, sinners in previous lives, entering into other bodies. Reprinted with permission from The Jewish Religion: A Companion, published by Oxford University Press.
Reincarnation is the idea that a soul now residing in a particular body may have resided in the body of another person in an earlier period of time. Theories of reincarnation or metempsychosis are found in many religions and cultures, ancient and modern, but there are no references to the idea in the Bible or the Talmud and it was unknown in Judaism until the eighth century CE, when it began to be adopted by the Karaites [a sectarian Jewish group] (possibly, it has been suggested, under the influence of Islamic mysticism).
The Philosophers Were Scornful
The usual Hebrew term for reincarnation is gilgul, "rolling," that is, the soul "rolls" through time from one body to a different body. The earliest [non-Karaite] reference to the doctrine is that of Saadiah [882-942] (Beliefs and Opinions, vi. 8). Saadiah writes:
"Yet I must say that I have found certain people, who call themselves Jews, professing the doctrine of metempsychosis, which is designated by them as the theory of the 'transmigration' of souls. What they mean thereby is that the spirit of Reuben is transferred to Simeon and afterwards to Levi and after that to Judah. [These names are generic, like Tom, Dick and Harry; no reference to the sons of Jacob is intended. Ed.] Many of them would even go so far as to assert that the spirit of a human being might enter into the body of a beast or that of a beast into the body of a human being, and other such nonsense and stupidities."
We learn incidentally from Saadiah's discussion that one of the reasons these people believed in reincarnation (this reason resurfaces in the Kabbalah) was because of the theological difficulties in God allowing little children to suffer. That they do, it was argued, is because of sins they had committed in a previous existence.
Among the other medieval thinkers, neither Judah Halevi [died 1141] nor Maimonides [1135-1204] makes any mention of the doctrine. Albo [15th century] (Ikkarim, vi. 20) refers to the doctrine only to refute it. He argues that the whole purpose for which the soul enters the body is to become a free agent, but once a soul has become a free agent why should it return to occupy another body? It is even more unlikely, says Albo, that human souls transmigrate into the bodies of animals.