religion. When returning to Judaism, these individuals would be expected to abandon their previous practices and adopt Jewish customs. The same rules in principle apply to the matrilineal descendants of such persons, though some rabbinical authorities may require stricter proof of Jewish descent than others. Whether such persons are required to undergo a full formal conversion depends on the community and their individual circumstances. For example, a male who has had a brit milah, who has a general understanding of Judaism, but who has been raised in a secular home might not be required to undergo ritual conversion. However, a male who has not had a brit milah, a male or female who has converted to or been brought up in another religion, or an individual raised in a completely secular home without any Jewish education, in most communities, may be required to undergo a full ritual conversion. For full participation in the community (for example, to marry with the participation of a rabbi), they may be required to display sincerity, such as a declaration of commitment to Judaism. Another example of the issues involved is the case of converts to Judaism who cease to practice Judaism (whether or not they still regard themselves as Jewish), do not accept or follow halakha, or now adhere to another religion. Technically, such a person remains Jewish, like all Jews, provided that the original conversion is valid. However, in some recent cases, Haredi rabbinical authorities, as well as the current Religious Zionist Israeli Chief Rabbinate, have taken the view that a given convert's lapse from Orthodox Jewish observance is evidence that he or she cannot, even at the time of the conversion, have had the full intention to observe the commandments and that the conversion must therefore have been invalid. A valid Jewish court of sufficient stature has the ability to revoke a person's or a group's status as Jews. This was done for the lost Ten Tribes of Israel and the Samaritans. Religious definitions Halakhic perspective According to the traditional Rabbinic view, which is maintained by all branches of Orthodox Judaism and Conservative Judaism, and some branches of Reform Judaism, only halakha can define who is or is not a Jew when a question of Jewish identity, lineage, or parentage arises about any person seeking to define themselves or claim that they are Jewish. As a result, mere belief in the principles