Kav HaYashar by Rabbi Tzvi Hirsch Kaidanover: what it is, structure and influence
The Kav HaYashar (קב הישר), “The Just Measure,” is a mussar (ethics) work by Rabbi Tzvi Hirsch Kaidanover (c. 1648–1712), a rabbi of Frankfurt. Wikipedia describes it as an ethical-kabbalistic collection of stories, moral guidance and customs, and a guide to God-fearing piety and to preserving the norms of the community.
Quick facts
| Title | Kav HaYashar (“The Just Measure”) |
| Author | Rabbi Tzvi Hirsch Kaidanover (c. 1648–1712; the birth date lacks a citation on Wikipedia) |
| First edition | Frankfurt am Main, 1705 |
| Chapters | 102 |
| Language | Hebrew; the author also prepared a Yiddish version |
| Genre | Jewish ethics (mussar) with kabbalistic elements |
The title
According to Wikipedia, kav is also the number of chapters of the work, 102, by its numerical value. And the author’s middle name, Hirsch, is an anagram of haYashar. Sefaria records both explanations: the title alludes to the number of chapters (קב = 102) and to the author’s name (הישר = הירש).
Content
It gathers stories, moral guidance and customs. Its teachings revolve around individual providence and the reckoning of sins and merits. It also reflects a kabbalistic dualism that divides reality according to its affinity with the divine or with impurity. It draws on the Yesod Yosef, a mussar work by his teacher Yosef Yoske of Dubno, infused with the Kabbalah of the Arizal: see the biography of the Arizal.
Editions and translations
- It was first published in Frankfurt in 1705. It had more than eighty editions, in nearly every country with Jewish communities (a claim without citation on Wikipedia; Sefaria also speaks of more than eighty editions).
- The Yiddish version prepared by the author himself had at least ten editions.
- A Ladino translation was printed in Istanbul, during the reign of Sultan Abdülaziz, by the Armenian publisher Tatyos Divitchiyan.
Influence
Wikipedia describes it as one of the most popular mussar works, and says that it comforted the Jewish communities of Europe after the Chmielnicki massacres of 1648–1649.
Frequently asked questions
What does Kav HaYashar mean?
“The just measure”; the title alludes to the number of chapters (102) and to the author’s name.
How many chapters does it have?
One hundred and two.
When was it printed?
In Frankfurt, in 1705.
Sources
- Kav HaYashar, reference article (English Wikipedia)
- Kav HaYashar, entry on Sefaria