Kol Bo (Hebrew: כל-בו, 'all is in it') is a collection of Jewish ritual and civil laws.
115), there comes a miscellaneous collection, containing the "takkanot" of R. Gershom and of Rabbeinu Tam, the Ma'aseh Torah of Judah haNasi, the legend of Solomon's throne, the legend of Joshua b. Levi, a kabbalistic dissertation on brit milah, a dissertation on gematria and noṭariḳon, 61 decisions of Eliezer ben Nathan; 44 decisions of Tashbetz, decisions of Isaac of Corbeil, and responsa of Peretz ha-Kohen, decisions of Isaac Orbil, of the geonim Naṭronai, Hai Gaon, Amram Gaon, Nahshon Gaon, laws of the mikveh taken from Perez's Sefer ha-Mitzvot, responsa, and finally the law of excommunication of Nahmanides.
Joseph Caro, in saying that the words of the Kol Bo are identical with those of the Orḥot Ḥayyim of Aaron ben Jacob ha-Kohen (14th century), seems to have suggested that the Kol Bo is an abridgment of the Orḥot Ḥayyim.
This is also the opinion of the Chida, and according to Aaron Schlitzstadt, the epitomizer was a certain Shemariah b. Simḥah, in the 14th century;[2] others think that it was Joseph ben Tobiah of Provence.
Zunz[6] refutes Benjacob's arguments, his opinion being that the Kol Bo is a compendium of the Orḥot Ḥayyim.