Rabbi Yehuda Ashlag (1885–1954) or Yehuda Leib Ha-Levi Ashlag (Hebrew: רַבִּי יְהוּדָה לֵיבּ הַלֵּוִי אַשְׁלַג), also known as the Baal Ha-Sulam (Hebrew: בַּעַל הַסּוּלָם‎, "Author of The Ladder") in reference to his magnum opus, was an Orthodox rabbi, kabbalist and anarchist born in Łuków, Congress Poland, Russian Empire, to a family of scholars connected to the Hasidic courts of Porisov and Belz.

In addition to his Sulam commentary on the Zohar, his other primary work, Talmud Eser Sefirot is regarded as the central textbook for students of Kabbalah.

[1] He spent the first few years living anonymously, supporting his family through manual labor by day and writing his commentaries at night.

Their views about Kabbalah ran contrary to Ashlag's experience with the teaching as a means of profound personal transformation and spiritual illumination, by becoming a vessel for divine light.

During this period, Ashlag also began one of his main works, Talmud Eser Sefirot, a commentary on all the writings of Isaac Luria.

In the 1930s Ashlag, now in his fifties, gathered around him a group of disciples, including Rav Yehuda Tzvi Brandwein, his closest student, and studied Kabbalah every night, often from shortly after midnight until dawn.

[1] Ashlag went to great lengths to publish Kabbalistic material in media suitable for disseminating the knowledge he had acquired across the entire nation.

[2][4] In 1943, Ashlag moved to Tel Aviv, and there began working on his book, HaSulam (The Ladder), a collection of commentaries on The Zohar.

During this period, he wrote for eighteen hours a day, and due to a lack of money he was not able to afford a sufficient amount of paper and ink to write more precise explanations.

His vast knowledge of the Lurianic system of Kabbalah enabled him to codify and edit the entire writings of the Ari HaKadosh, Rabbi Yitzchak Luria.

The first, Talmud Eser Sefirot is a complete re-editing and commentary to the works of 16th century Kabbalist Rabbi Isaac Luria.

This is a comprehensive exposition of the system of the upper worlds, Partzufim and Sefirot, in the scientific language of Kabbalah which was developed by Luria.

[2] As a core Kabbalistic text, it is especially unique in its utmost precision to detail to the structural organization and processes occurring in the upper worlds.

This was the first since the 18th century when the Baal Shem Tov, Moshe Chaim Luzzatto, the Vilna Gaon and Shalom Sharabi offered their interpretation of Luria's teaching.

Though his anti-capitalist and anti-imperialist ideas show some Marxist influence, he strongly opposed communism instituted by force and believed in "developing a community based on love between its members and a society founded on economic justice.