Tendler voiced his objection to the tactics employed by the
New York divorce coercion gang, an outfit of rabbis that utilized kidnapping, and sometimes torture, to force Jewish men to grant their wives
religious divorces, saying "The idea that a
beth din can issue an order for coercion is baloney, a hoax." While conceding that he had had previous dealings with Mendel Epstein, a leader of that group, Tendler nevertheless characterized him as being "unreliable". Regarding Martin Wolmark, another member of that group, Tendler stated, "He's a very intelligent fellow, and he's American. I can't imagine him getting involved in such a dirty business." Epstein was later convicted of conspiracy to commit kidnapping, and Wolmark was convicted of conspiracy to commit extortion. Tendler was responsible for the fact that modern-day Orthodox Jews in the United States and Israel generally do not consider
swordfish to be a
kosher fish. In order to be considered kosher under biblical law, fish must have both fins and scales, and while swordfish are born with scales, they shed them as they grow into adulthood. Orthodox opinion began to shift in 1951, after Tendler examined swordfish and decided that it was not kosher due to the lack of scales. Tendler's opinion provoked strong debate among halakhic authorities during the 1960s. Among Mediterranean Jews, however, there was a longstanding tradition (
minhag) of considering swordfish kosher. Swordfish was, and possibly still is, consumed by Jews in
Italy,
Turkey,
Gibraltar,
Morocco,
Tunisia, and
England ==Published works ==