Origins of Judaism
For centuries, the traditional understanding has been that Judaism came before Christianity and that Christianity separated from Judaism some time after the destruction of the Second Temple in 70 CE. Starting in the latter half of the 20th century, some scholars have begun to argue that the historical picture is quite a bit more complicated than that. In the 1st century, many Jewish sects existed in competition with each other, see Second Temple Judaism. The sects which eventually became Rabbinic Judaism and Early Christianity were but two of these. Some scholars have begun to propose a model which envisions a twin birth of Christianity and Judaism rather than a separation of the former from the latter. For example, Robert Goldenberg (2002) asserts that it is increasingly accepted among scholars that "at the end of the 1st century CE there were not yet two separate religions called "Judaism" and "Christianity"".
Daniel Boyarin (2002) proposes a revised understanding of the interactions between nascent Christianity and nascent Rabbinical Judaism in Late Antiquity which views the two religions as intensely and complexly intertwined throughout this period.
Jewish diaspora
Karaim are Jews who used to live mostly in Egypt, Iraq, and Crimea during the Middle Ages. They are distinguished by the form of Judaism which they observe. Rabbinic Jews of varying communities have affiliated with the Karaite community throughout the millennia. As such, Karaite Jews are less an ethnic division, than they are members of a particular branch of Judaism. Karaite Judaism recognizes the Tanakh as the single religious authority for the Jewish people. Linguistic principles and contextual exegesis are used in arriving at the correct meaning of the Torah. Karaite Jews strive to adhere to the plain or most obvious understanding of the text when interpreting the Tanakh. By contrast, Rabbinical Judaism regards an Oral Law (codified and recorded in the Mishnah and the Talmud) as being equally binding on Jews, and mandated by God. In Rabbinical Judaism, the Oral Law forms the basis of religion, morality, and Jewish life. Karaite Jews rely on the use of sound reasoning and the application of linguistic tools to determine the correct meaning of the Tanakh; while Rabbinical Judaism looks towards the Oral law codified in the Talmud, to provide the Jewish community with an accurate understanding of the Hebrew Scriptures.