Chofetz Chaim Daily 15 Teves 8:1 Asur to say Avak rechilus – negative implication (e.g. to tell R how ploni said lets not talk about what R did). 2) Praise that will cause hard feelings is also avak rechilus (e.g. to praise one before his spouse or partner about their charity giving; it will make the other think they’re wasting their money). 3) Asur to tell someone who refused you a favor, ploni told me that you did HIM similar favor because it will make him upset at ploni.
Chofetz Chaim Daily 7 Teves 6:1 Asur to believe rechilus even if it was said in the presence of many people. 6:2 Asur to believe rechilus even if said in front of the subject. If he doesn’t protest, it doesn’t mean he agrees to the story. Anyway, why believe someone who’s saying useless info & committing many sins, to ruin the reputation of a good person?!
Chofetz Chaim Daily 5 Teves 5:5 The Chofetz Chaim bemoans the widespread practice of people asking others what ploni said about him & ploni’s opinion of him. It is destructive behavior and transgresses many negative commandments.