First edition of this kabbalistic commentary on the divine name (Tetragrammaton) by R. Abraham ben Alexander (Axelrad) of Cologne. In Keter Shem Tov the author attempts to achieve a synthesis between the mysticism of the Jewish pietists (Ḥasidim) in Germany based on combinations of letters and numbers, and the Kabbalah of the Sefirot (with which he had become acquainted in Provence or in Spain). His text is composed of a short summary of his system and represents a kind of cosmological symbolism that relies on the conclusion provided by R. Abraham Ibn Ezra in his Sefer ha-Shem, as well as on the statements of the kabbalists R. Ezra and R. Azriel.

R. Abraham ben Alexander (Axelrad) of Cologne (13^th century), a kabbalist, was a disciple of R. Eleazar b. Judah of Worms, he immigrated to Spain where he probably studied with the kabbalist R. Ezra. R. Solomon ben Abraham Adret knew him personally in his youth, and tells of his extraordinary oratorical gifts, and the interesting material in his sermons (Responsa no. 548). Althought Keter Shem Tov, which is extant in numerous manuscripts, was first published independently in Amsterdam in 1810, it also appeared under the title Ma'amar Peloni Almoni in the collection of writings Likkutim me-Rav Hai Gaon (1798). A new edition was published by Jellinek (1853). In R.Samson ben Eliezer's work Barukh she-Amar (1795), Keter Shem Tov is attributed to R. Menahem Ashkenazi, another disciple of R. Eleazar of Worms. Benjacob is wrong in stating that there is another work entitled Keter Shem Tov by Abraham consisting of a mystic commentary to Psalms, Joshua, and Judges. The actual date of publication is unclear, some bibliographies dating it 1812 or 1815.

R. Solomon ben Adret relates (Teshuvah, i. No. 548) that he saw Abraham when he came to the king of Castile, probably Ferdinand II. (the Saint). On this occasion Abraham assumed the name of Nathan to conceal his identity. R. Adret also claims to have heard from an old man that R. Abraham of Cologne preached on Num. vii. 1, in the house of R. Adret’s father before a great many eminent rabbis, and displayed much erudition.