In his 17th volume of Mishne Halachos, Klein names people who believe the Lubavitcher Rebbe, Rabbi Menachem M. Schneerson, is still alive, as “Apikoras.”
The spiritual leader of the Ungar community head of the Bais Shearim Yeshiva in Brooklyn, Klein knew the Rebbe before he assumed leadership of the Lubavitch movement.
“This sect of crazies, which falsify the Torah and our sages’ words, to say the Moshiach is dead but is really alive… these are things against our holy Torah.”
His sharp words are an answer to a messianic booklet, which is not identified by name.
Klein continues to write: “Whoever can, should as soon as possible, silence and stop the proclamations after or before the prayers ‘Yechi… King Moshiach’ which is a disgrace to the Rebbe OBM.”
He ended his attack with a plea: “My intentions are holy – not to destroy the big building the Rebbe OBM built for over 50 years.. may he be an advocate for us and for all the Jewish people, especially his students and Chasidim.”