מְכַסֶּ֣ה שִׂ֭נְאָה שִׂפְתֵי־שָׁ֑קֶר וּמוֹצִ֥א דִ֝בָּ֗ה ה֣וּא כְסִֽיל׃
He that hideth hatred is of lying lips; And he that uttereth a slander is a fool.
Rashi on Proverbs
He who covers up hatred has false lips The flatterer has false lips, and he hides hatred in his heart.
Rashi on Proverbs
and he who spreads slander is a fool Heb. דבה, a rumor about his friend, about which people will converse (דובבין).