It's a requirement of the Jewish law court, should there ever be one,
and should anyone ever be convicted of adultery by it. It is not a requirement of an individual. Nobody is ever declared non-Jewish for not ever having stoned someone. That would actually require someone to commit adultery before it were possible for anyone to become Jewish, which would be absurd.
(
Moon Girl Technologies horrendous beanbag, Sat 14 Jul 2012, 0:05,
Reply)