Q. Does a rabbi have professional privilege in Jewish law?
A. The general principle of Jewish ethics is that a one must respect the privacy of other people. If you are told something in confidence you must respect that confidence unless the person concerned permits you to reveal the information; the Torah says, “You shall not go as a tale-bearer amongst your people” (Lev. 19:16).
Rabbi Eliezer Waldenberg in his responsa Tzitz Eliezer, volume 13, no. 81, says that a Beth Din may compel the giving of testimony which might otherwise involve a breach of personal or professional confidence, because of the Torah verse, “He who is a witness, if he does not tell, he bears his iniquity” (Lev. 5:1). However, such testimony would probably have to be given in camera in order to prevent it being heard by anyone who has no “need to know”.