I forget where it is, it’s towards the end of either O.C 2, 3, or 4
It’s in Yoreh Deiah 2:109:
??? ???? ????????? ?? ???????? ????? ??? ????? ????? ????? ??????? ??????? ?????? ??? ?? ???????? ?????? ???? ?????? ????? ??? ??????? ???? ??? ???? ????? ????? ????? ???? ?? ????? ???? ????? ??? ???? ???? ????? ???? ????? ????? ?? ?????? ????? ?? ?? ???? ????? ??? ??? ?????? ?? ???? ?????? ??????? ?????? ??? ?? ??????? ???? ???? ??? ??? ???? ???? ????? ?? ???? ?????? ??? ????? ???? ??? ??????? ????? ??? ??? ?????????? ??? ?? ????????? ??????? ?? ??? ????? ??????? ??? ?????? ?? ???? ???? ???? ??????? ?????? ?? ??????? ??? ???? ??????? ??? ??? ??? ????? ???? ????? ?? ?? ???? ?????? ???? ???? ????? ???? ??? ?????? ???? ???? ????? ????? ?????? ??”? ??? ????? ???? ??? ????? ???? ???? ????? ??? ??? ?????? ??? ???? ???? ???? ??? ?? ???? ??? ???? ???? ?? ????? ????? ?????? ?? ?????? ????? ???? ???? ??? ??? ???? ???????? ?? ??????
?????
??? ?????????
See also Orach Chaim 5:12:3 where he writes:
???? ?? ???? ????? ???? ????? ????? ???? ???? ?? ??? ???? ??? ???? ?????? ???? ????? ??? ???? ????? ??? ???? ???? ????? ???? ????? ????? ????? ????? ????? ????? ????? ?? ????? ??? ???? ??????
????? ???? ?? ??????? ??????? ???????? ??? ?????? ???? ??? ?? ???? ???? ?????? ?? ????? ???? ???? ?????? ?? ??? ??? ???? ?? ??? ?????? ???? ????? ??????? ???? ?????? ??? ????? ?????? ????? ????? ???? ???? ??? ?? ?? ????? ??? ???? ???? ????? ??? ???? ???? ?? ??? ????