Who is a Jew?

"Who is a Jew?" (Hebrew: מיהו יהודי‎‎ pronounced [ˈmihu jehuˈdi]) is a basic question about Jewish identity and considerations of Jewish self-identification. The question is based on ideas about Jewish personhood, which have cultural, religious, political, genealogical, and personal dimensions. According to Jewish law, a person is only considered Jewish if their mother is Jewish, or they underwent a proper conversion. Exceptions are made within Reform Judaism and Reconstructionist Judaism, which accept patrilineal descent.

The definition of who is a Jew varies according to whether it is being considered by Jews on the basis of religious law and tradition or self-identification, or by non-Jews for other reasons, sometimes for prejudicial purposes. Because Jewish identity can include characteristics of an ethnicity, a religion, or peoplehood, the definition depends on either traditional or newer interpretations of Jewish law and custom.

Israel's Law of Return stipulates that a Jew is someone with a Jewish mother or someone who has converted to Judaism. The Israeli Chief Rabbinate requires documents proving the Jewishness of one’s mother, grandmother, great-grandmother and great-great-grandmother when applying for marriage. The Office of the Chief Rabbi (OCR) has underlined the basic principle that a child is not recognised by the OCR and other bodies as Jewish unless his or her mother is Jewish.

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