Because the ḥasidic movement is rooted in its own particular understanding of Jewish mysticism, it is sometimes assumed that its opponents, the Mitnaggedim, were uninterested or even dismissive of kabbalah. But nothing could be further from the truth. The greatest of the Mitnaggedim, the Gaon of Vilna (Elijah ben Solomon Zalman, 1720-1797), diligently studied kabbalistic texts and wrote commentaries on them. Likewise his most famous disciple, Ḥayyim of Volozhin—perhaps the most influential East European rabbinic thinker of his day—focused much of his attention on mystical subjects.
Raphael Shuchat has recently edited and published a critical Hebrew edition of Rabbi Ḥayyim’s passing statements and answers to students’ questions, which were compiled by his disciples under the name Sh’iltot, and first published after his death. In an interview by Alan Brill, Shuchat comments:
Maybe the most interesting quote [in this work is that] Rabbi Ḥayyim says: “The Vilna Gaon said that the main effort of man [in striving for spiritual perfection] must be concerning transgressions between man and man in all their details.”
There are also interesting sources concerning the Ḥasidim. In [his major mystical-theological work], Nefesh ha-Ḥayyim, Rabbi Hayyim never mentioned the Ḥasidim by name, but . . . Sh’iltot points out ideological disagreements with Ḥasidism. It also makes clear that he was tolerant towards Ḥasidim in day-to-day life, permitting students with a ḥasidic inclination to study at the yeshiva. We discover that he had a grandson who became a Ḥasid.
Hayyim also frequently warned against ecstatic experiences and revelations, referring to them as coming from the “other side,” [a kabbalistic term for demonic or satanic forces].
The text also makes clear that, despite the stereotype of Mitnagged who studies only the Talmud to the exclusion of other religious works, that Rabbi Ḥayyim advocated for a well-rounded Jewish education, and considered it “imperative to study all of the Bible, Hebrew grammar, . . . midrash, aggadah, . . . and Zohar.”
Read more on Book of Doctrines and Opinions: https://kavvanah.blog/2021/08/23/interview-with-raphael-shuchat-on-r-hayyims-of-volozhins-conversations/