By Joel Davidi Weisberger | July 01, 2021 Before I get to Abraham Firkovich’s remarkable letter to the third Lubavitcher Rebbe, known by his magnum opus “the Tzemach Tzedek,” I’d like to address something. People sometimes ask me (yes, I mean you, Mom) about the nature of my interest in the Karaites and Karaism, so I’d like to take this opportunity to relay my thoughts on the subject. As a young boy studying in yeshiva I was provided with a decent well-rounded education, but still I always felt that there was something missing. Tanach wasn’t studied so I made it my mission to go through it on my own. The same goes for Jewish history: I devoured every book on the subject. Since I was always fascinated by Jewish history, I had come across the Zadokim and the Karaites (although sharing quite a few similarities, the Zadokim were active during the Second Temple whereas the Karaites came on the scene in the Middle Ages. The terms were often interchangeable, with rabbis [e.g., Raabad, Ibn Ezra et al] often referring to Karaites as Zadokim) at a young age and was fascinated by this group of schismatics who apparently were still around. What did they believe? How did they come about, and why? As I delved more into it I realized that there was a lacunae in my education; nobody had ever bothered to tell me that quite a few things that we regard today as normative halacha came about in reaction to the Karaite heresy, or as Chazal put it להוציא מלבן של צדוקים. Two examples will suffice for now: 1) The emphasis on eating cholent/hamin on Shabbat afternoon is a fairly late innovation and it was clearly designed to offset the Karaite prohibition of letting a fire burn into the Sabbath (a stance that most Karaites eventually abandoned, by the way). 2) The blessings before lighting the Sabbath candles is also a late innovation that is not mentioned in the Mishnah or the Talmud, but rather comes into being during the Geonic Period when Karaism formed the greatest challenge to normative Rabbinic Judaism. The blessing on the Sabbath candles (as well as the custom to recite “Bameh Madlikin” on Friday eve) deserves a separate treatment, but it was clearly a reaction to the Karaite antipathy toward having a fire burn into Shabbat.