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 religious movements
The very idea of Jewish denominationalism is contested by some Jews and Jewish non-denominational organizations, which consider themselves to be "trans-denominational" or "post-denominational". A variety of new Jewish organizations are emerging that lack such affiliations:Organizations such as these believe that the formal divisions that have arisen among the "denominations" in contemporary Jewish history are unnecessarily divisive, as well as religiously and intellectually simplistic. According to Rachel Rosenthal, "the post-denominational Jew refuses to be labeled or categorized in a religion that thrives on stereotypes. He has seen what the institutional branches of Judaism have to offer and believes that a better Judaism can be created." Such Jews might, out of necessity, affiliate with a synagogue associated with a particular movement, but their own personal Jewish ideology is often shaped by a variety of influences from more than one denomination.