The most severe form of avak rechilus involves statements that reveal information which was told in confidence. (Sharing confidential information to save someone from harm will be discussed later.) Divulging secrets breeds a lack of self control in speech-related matters which leads to actual rechilus.
When publicizing a secret could prove damaging, doing so would constitute speaking both avak rechilus and actual loshon hora. Even when no damage was foreseen, the mere violation of confidentiality renders one a “holech rochil,” gossipmonger.
