In terms of social relations, most secular Jews view their Jewish identity as a matter of culture, heritage, nationality, or ethnicity. Ancestral aspects can be explained by the many Jews who view themselves as atheists and are defined by matrilineal descent or a Cohen (Kohen) or Levi, which is connected by ancestry. The question of "who is a Jew" is a question that is under debate. Issues related to ancestral or ethnic Jews are dealt with by the Israeli Chief Rabbinate.