Judaism
There are some movements that combine elements of Judaism with those of other religions. The most well-known of these is Messianic Judaism, a religious movement, which arose in the 1960s, that incorporates elements of Judaism with the tenets of Christianity. The movement generally states that Jesus is the Jewish Messiah, that he is one of the Three Divine Persons, and that salvation is only achieved through acceptance of Jesus as one's savior. Some members of the movement argue that Messianic Judaism is a sect of Judaism. Jewish organizations of every denomination reject this, stating that Messianic Judaism is a Christian sect, because it teaches creeds which are identical to those of Pauline Christianity.
Judaism
Like the Sadducees who relied only on the Torah, some Jews in the 8th and 9th centuries rejected the authority and divine inspiration of the oral law as recorded in the Mishnah (and developed by later rabbis in the two Talmuds), relying instead only upon the Tanakh. These included the Isunians, the Yudganites, the Malikites, and others. They soon developed oral traditions of their own, which differed from the rabbinic traditions, and eventually formed the Karaite sect. Karaites exist in small numbers today, mostly living in Israel. Rabbinical and Karaite Jews each hold that the others are Jews, but that the other faith is erroneous.