The gnosticizing theosophy of the Sefer ha-bahir and the contemplative mysticism of the masters of Languedoc became one in the hands of the Kabbalists in Catalonia, where the Jewish community of Gerona was a veritable seat of esoterism during the first half of the 13th century. To the school of Gerona belong, among others, masters such as Ezra ben Solomon, Azriel of Gerona, Jacob ben Sheshet, and Moses ben Naḥman (or Naḥmanides), the famous Talmudist, biblical commentator, and theologian. Their influence on the subsequent course of Jewish mysticism is of fundamental importance, though none of them left a complete synthesis of his theosophy. They expressed themselves, with more or less reserve, by means of commentaries, sermons, polemic or apologetic treatises, and brief summaries (at most) for the noninitiated. It is not impossible, however, to discover through these texts their vision of the world and to compare it with the views of the Jewish thinkers who attempted to harmonize the biblical-rabbinical tradition with Greco-Arab philosophy, whether of Neoplatonic or Aristotelian inspiration.
At the base of the Kabbalistic view of the world there is an option of faith: it is by a voluntary decision that the unknowable Deity—who is “nothing” or “nothingness” (nonfinite) because he is a fullness of being totally inaccessible to any human cognition—sets into motion the process that leads to the visible world. This concept radically separates Kabbala from the determinism from which the philosophy of the period could not, without contradiction, free the principle of being. In addition, it offers a solution consistent with faith to the problem of creation ex nihilo (out of nothing). The paradoxical reinterpretation of the concept of the “nothing” eliminates the original matter coeternal with God and solves the opposition between divine transcendence (remoteness from the world) and immanence (presence in the world); issuing from the unfathomable depth of the Deity and called to return to it, the world, visible as well as invisible, is radically separated from God, who is at the same time constantly present. The correspondence between the sefirot and all the degrees of being gives meaning to the structure of the world and to the history of humanity centred on the revelation given to the chosen people, a revelation that is a rule of life for this people and the criterion of merit and sin, or good and evil. Thus, from the top to the bottom of the ladder, there are corresponding realities that control one another. Contrary to the opinion of the philosophers, evil is also a reality since it is the rupture of the universal harmony. It is also the consequence of this rupture, in the form of punishment. From this perspective, scrupulous observance of the Torah, both in the written text and the oral tradition, is the essential factor for the maintenance of the universe. The “rational” motivation of the commandments, which raises insurmountable difficulties for the theologians of philosophical orientation, is in the eyes of the Kabbalists a false problem; the real problem is the fundamental nature of the Torah. Kabbala brings more than one solution to it, whereas philosophy has trouble providing a single coherent and comprehensive solution.
It follows from this general concept that the Jewish faith, with its implications—the conviction of holding the undiluted truth, the faithful preservation of ritual practices, and the eschatological expectation—is safeguarded from all the doubts that either philosophical speculation or the rival religious doctrines of Christianity and Islam could evoke in the minds of Jewish believers. Kabbala, already at the stage it had reached at Gerona, may be said to be a significant factor in the survival of Judaism, which was exposed everywhere in medieval society to a wide range of perils.
Besides the Gerona school and the doctrinal descendants of Isaac the Blind in Languedoc, there was another school of Jewish esoterism in southern Europe during the first half of the 13th century. Members of this school preferred to remain anonymous and therefore published their writings, such as the Sefer ha-ʿiyyun (“Book of Speculation”), either without an author’s name or with an attribution to a fictitious authority. Their speculation was directed to the highest levels of the divine world, where it discerned aspects beyond the 10 sefirot and attempted to give an idea of them by resorting to the symbolism of light, as well as to the primordial causes and the archetypes contained in the Deity or directly issuing from it. The sometimes-striking similarity between these speculations and those of the Christian theologian John Scotus Erigena (810–c. 877), whose work was revived in the 12th and 13th centuries, suggests not only a kinship of themes between this Kabbalistic current and Latin-language Christian Neoplatonism but also a concrete influence of the latter upon the former. The same may be true of Isaac the Blind and the school of Gerona, but certain knowledge is lacking. Sefer ha-temuna
The anonymous writer of the Sefer ha-temuna (“Book of the Image”) provided literary expression for another manifestation of Jewish mysticism in this period. This very obscure document claims to explain the figures of the letters of the Hebrew alphabet. The speculation of this treatise bears on two themes that were not foreign to the school of Gerona, but it develops them in a personal manner that decisively influenced the future of Jewish theosophy. On the one hand, it deals with a theory of the different cycles through which the world must travel from the time of its emergence to its reabsorption into the primordial unity. On the other hand, it addresses various readings that correspond to these cycles in the divine manifestation that is constituted by the Scriptures. In other words, the interpretation and consequently the message of the Torah vary according to the cycles of existence; the passage to a cycle other than that under whose governance humanity is presently living could thus entail the modification, even the abrogation, of the rule of life to which the chosen people are presently subject, an explosive notion that threatened to overthrow the Jewish tradition. Medieval German (Ashkenazic) Hasidism
The period during which Kabbala was established in the south of France and in Spain is no less important for the shaping of Jewish mysticism in the other branch of European Judaism, which was situated in northern France (and England) and in the Rhine and Danube regions of Germany. Unlike medieval Kabbala, which experienced a broad and varied development starting in the second half of the 13th century, the movement designated as German, or Ashkenazic (from a biblical place-name conventionally used to designate Germany), Hasidism hardly survived as a living and independent current beyond the second quarter of the 13th century (it has no connection with modern Hasidism). Franco-German Judaism experienced a certain continuity of mystical tradition, based on the Sefer yetzira and the hekhalot (see above Sefer yetzira); certain elements of theurgy and magic of Babylonian origin may also have reached it through Italy; and apparently the gnosticizing current that was crystallized in the Sefer ha-bahir did not pass without leaving traces in Germany. The intellectual atmosphere of Franco-German Judaism, however, differed greatly from that reigning in Spain or even Provence and Languedoc. It was characterized by an almost exclusively Talmudic culture, less intellectual contact with the non-Jewish environment than in the countries of Muslim civilization, and a very limited knowledge of Jewish theology in Arabic from the Middle East, North Africa, and Spain. This situation did not change until the last third of the 12th century; until then, the “philosophical” equipment of the Franco-German Jewish scholar consisted essentially of a Hebrew paraphrase, dating perhaps from the 11th century, of the treatise Beliefs and Opinions by Saʿadia ben Joseph (the great 9th–10th-century Babylonian Jewish scholar and philosopher) and the commentary on the Sefer yetzira written in Hebrew in 946 by the Italian physician Shabbetai Donnolo (born 913). Even when the cultural influence of Spanish Judaism came to be felt more strongly in France, England, and Germany, speculative Kabbala hardly penetrated there. Franco-German Jewish thinkers who inclined toward theological speculation had their own problems—notably the persecutions that began during the First Crusade—which resulted in a mysticism strongly imbued with asceticism.