“The human soul is essentially different from the animal soul; Nahmanides adopts, along with other kabbalists of the earliest period, the Platonic view of the soul, according to which there exist different souls in man and not only different faculties of a unitary soul.
According to Nahmanides, man’s anima rationalis unites the rational and the mystical-intuitive, and hence he sees no need for further distinctions. Nevertheless, the weight shifts imperceptibly to the second side: the highest soul, neshamah, which comes from binah and yesod, is the mediator of prophecy, and through it man, in the state of debhequth, attains communion with the deity as a result of the longing for its origin implanted in it.
Enoch and the three Patriarchs, Moses, and Elijah had achieved this supreme state already on earth; however, it is not a full unio mystica with the deity but rather a communio, as we have argued at length in our discussion of the subject of kawwanah.
In the prophetic vision, during which the soul is united with the objects of its contemplation, it is in this state of debhequth, that it obtains a ”knowledge of God face to face.” In this longing for its origin, the highest soul of man becomes capable of penetrating all the intermediary spheres and rising up to God by means of its acts—which, strangely enough, are united here with contemplation.
The eclectic manner in which the kabbalists adopted philosophical doctrines concerning the soul is also apparent in the fact that Azriel, for example, accepts the Aristotelian definition of the soul as the form of the body, seemingly unaware of the contradiction between this idea and important kabbalistic doctrines.
The contradiction results from the adoption and further development of the doctrine of metempsychosis. While this doctrine is rather openly propounded in the Book Bahir, as we saw on p. 188ff., it is treated, strangely enough, as a great mystery in Provence and in Gerona.
The authors without exception speak of it only in hints and in veiled allusions. They make no attempt to account for this idea but presuppose it as a truth handed down by esoteric tradition.
The term gilgul, generally used at a later date for the transmigration of souls, seems to be as yet unknown among these early authors. Instead, they prefer to speak of sod ha-‘ibbur. This term, literally “secret of impregnation,” is used in the Talmud for the methods of computing the calendar, handed down only orally for a long time, the idea being that the leap years were impregnated, as it were, by the addition of an extra month.
But ‘ibbur can, if necessary, also be understood as “transition,” and it is doubtless in this sense that the term was picked up by the kabbalists. The “secret of the ‘ibbur” is that of the passage of the soul from one body to another and not, as among the later kabbalists, a real phenomenon of impregnation through which, after birth an additional soul sometimes enters into the one originally born with a person.
We still do not know what led the kabbalists of the first generation to treat this doctrine in such a strictly esoteric manner and what danger they saw in exposing it to the public. It is most unlikely that fear of the Catholic Church, which had officially condemned this doctrine, was a factor.
Where no christological elements were involved, Jewish theology generally had no inhibitions. The polemics directed by the philosophers against this doctrine should likewise have stimulated controversy rather than secrecy. Nahmanides had no lack of opportunity to denounce the philosophic criticism of this doctrine. Instead, he retreated into extremely prudent, and for the uninitiated, often impenetrable statements in his commentary on the book of Job, the key to which, according to the kabbalists of Gerona, lay precisely in the doctrine of metempsychosis.”
Gershom Scholem, Origins of the Kabbalah, pp. 456-7.