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, ethnic religious, political, genealogical, and personal dimensions. Orthodox Judaism and Conservative Judaism follow the Halakha, deeming a person to be Jewish if their mother is Jewish, or they underwent a proper conversion. Reform Judaism and Reconstructionist Judaism accept both matrilineal and patrilineal descent. Karaite Judaism predominantly follows patrilineal descent.

Jewish identity is also commonly defined through ethnicity. Opinion polls have suggested that the majority of Jews see being Jewish as predominantly a matter of ancestry and culture, rather than religion.Ashkenazi Jews, being the most numerous Jewish ethnic division, have been the subject of numerous genealogical studies and have been found to be a distinct, homogeneous ethnic group. However, other studies have found overlap between Ashkenazi Jews, Italians and Greeks.

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.

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