"Adass Jeshurun, Adas Jisroal was originally the breakaway minority of Orthodox congregations in Germany in the mid-19th century. These congregations dissociated themselves on religious grounds from the unitary congregations established by state law in which the majority tended toward Reform Judaism.
"The main aim of this branch was to safeguard strict adherence to Jewish law. The Hebrew terms Adass (or Adat, Adath) Jeshurun and Adass Jisroel, meaning "congregation of Jeshurun" and "congregation of Israel," were chosen by these congregations to express their conviction that, even if in the minority, they were the "true Israel." The names were cherished for their socioreligious connotations by Orthodox groups in the West where Reform Judaism was widespread.
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