The second work is the Perush R. Eliezer on Sefer Yezirah. R. Eleazar ben Judah of Worms was a scholar in the fields of halakhah, theology, and exegesis in medieval Germany. Eleazar was the last major scholar of the Hasidei Ashkenaz movement. Born in Mainz, he traveled and studied in many of the centers of learning in Germany and northern France. He spent most of his life in Worms. Eleazar was a member of the Kalonymus family, one of the most important German-Jewish families of that period. His father R. Judah b. Kalonymus, one of the leading scholars of his generation, taught his son both halakhah and esoteric theology. R. Judah b. Samuel, he-Hasid ("the Pious"), the leading figure in the Hasidei Ashkenaz movement, to whom Eleazar was related, was, however, his main teacher in the latter field and R. Moses ha-Kohen and R. Eliezer of Metz were his most prominent teachers in halakhah. Eleazar witnessed and suffered personally from the new outburst of persecution of the Jews by the Crusaders at the end of the 12th and the beginning of the 13th century. On a number of occasions in his commentary on the prayers, one of his major works, he noted the events that befell Worms, especially during the persecutions that followed the fall of Jerusalem to Saladin. In one of these persecutions, Eleazar's wife, daughter, and son were murdered, and he was severely injured. Eleazar's halakhic book Sefer ha-Roke'ah (Fano, 1505; reissued several times) followed the tradition of halakhic works of the tosafists of northern France and Germany. The book was intended to educate the common reader in the details of halakhic law. His major theological work was Sodei Razayya ("Secrets of Secrets"). Four parts of this work were printed, although most of what is extant is found only in manuscripts. The first part, a study of the creation (Sod Ma'aseh Bereshit), describes how the earth, stars, elements, etc., were created. Eleazar wrote this part of his work as an exegesis based on the 22 letters of the Hebrew alphabet. This was in accordance with his belief (derived from Sefer Yezirah) that the alphabet, the word of God, was the source of existence. Eleazar included in this part ancient material from the Heikhalot and Merkabah literature especially the Baraita de-Ma'aseh Bereshit and Shi'ur Komah. Appended to this work,without a title page, is Derekh Edosekhah on Joshua and Bereshit.

דף [10-3,א]: זרע גד (הקדמה באגדה נאה לדרוש בשמחת תורה לחבר ולקשר סיום התורה בתחילתה). דף [10,א-12,א]: "איגרת יחוסנו אשר סידר ... מ' נתן נטע (סג"ל לאנדא ז"ל שהי' רב באושפצין)... עד מהר"ל מפראג ... והילך המגילת יוחסין מספר מט"מ (מטה משה על התורה) שחיבר ... מ' משה כ"ץ ז"ל ...ונספח אליו מגילת יוחסין מבנו הרב מהר"י [חתנו ר' יצחק כ"ץ], אשר הועתק בפראג ע"י הרב מ' מאיר פערילש... ונדפס בזאלקאווא בשנת תק"ה". עי' כ"ץ, משה בן ישעיהו הכהן. "תיקונים והערות" לספר, פרסם המחבר בספרו כנף רננה, חלק א.

הסכמות: ר' שמעון בה"ג מהרמ"ס [ר' משה סופר], מקראקא, וויען, ו צו תרמ"ב; ר' יצחק שמעלקעס, פרעמישלא, ג משפטים תרמ"ב (עם הערה); ר' שלמה הלברשטאם, ווישניצא (עם הערה); ר' אברהם יהודה הכהן שווארץ, מאד, ח אדר תרמ"ב; ר' יקותיאל יהודה ט"ב [טייטלבוים], (סיגוט. עם הערה); ר' מנחם מענדל פאנעט, דעש, ד תרומה תרמ"ב (עם הערה).