As a scholar of modern Jewish history, religion and politics, I am often asked to explain the differences between Judaism’s major denominations. Here is a very brief overview: Rabbinic roots Two thousand years ago, Jews were divided between competing sects all based on the Jewish scriptures, but with different interpretations. After the Romans destroyed the Jerusalem Temple in 70 C.E., one main group, who called themselves “rabbis” – sages or teachers – began to dominate. What we now know as “Judaism” grew out of this group, technically called “Rabbinic Judaism.” Rabbinic Judaism believed that God gave Jewish teachings and scriptures...