Who are we to judge?
Halacha is that we must judge. We have to know whose wine not to drink and who not to count in minyanim among a number of other halachic issues. The Chofetz Chaim tells us to judge who is an apikorus:
“???? ???? ?????? ???? ??? ??? ?’ ???? ?’ – ????: “???? ?????? ?????? ??? ??? ????????? ????? ?????? ??????? ??? ?????? ???? ??? ??????”.
??????- “???????? ???? ????? ?????… ?????? ??? ???? ?? ????? ???? ?? ????? ??? ????? ???…”