Judaism
Christianity was originally a sect of Second Temple Judaism, but the two religions diverged in the first century. The differences between Christianity and Judaism originally centered on whether Jesus was the Jewish Messiah but eventually became irreconcilable. Major differences between the two faiths include the nature of the Messiah, of atonement and sin, the status of God's commandments to Israel, and perhaps most significantly of the nature of God himself. Due to these differences, Judaism traditionally regards Christianity as Shituf or worship of the God of Israel which is not monotheistic. Christianity has traditionally regarded Judaism as obsolete with the invention of Christianity and Jews as a people replaced by the Church, though a Christian belief in dual-covenant theology emerged as a phenomenon following Christian reflection on how their theology influenced the Nazi Holocaust.
Origins of Rabbinic Judaism
Although the Rabbis traced their origins to the Pharisees, Rabbinic Judaism nevertheless involved a radical repudiation of certain elements of Pharisaism—elements that were basic to Second Temple Judaism. The Pharisees had been partisan. Members of different sects argued with one another over the correctness of their respective interpretations, see also Hillel and Shammai. After the destruction of the Second Temple, these sectarian divisions ended. The term "Pharisee" was no longer used, perhaps because it was a term more often used by non-Pharisees, but also because the term was explicitly sectarian. The Rabbis claimed leadership over all Jews, and added to the Amidah the "birkat haMinim" (see Council of Jamnia), a prayer which in part exclaims, "Praised are You O Lord, who breaks enemies and defeats the arrogant," and which is understood as a rejection of sectarians and sectarianism. This shift by no means resolved conflicts over the interpretation of the Torah; rather, it relocated debates between sects to debates within Rabbinic Judaism.