One might come to degrade the sin of forbidden speech as he might not realize that derogatory speech includes talk that is true, or, he might think that it is permitted to mention a flaw in ones character, or likewise, he might not realize that believing forbidden speech only in his heart is also a sin. Likewise, one might come to speak badly about another as his evil inclination will convince him that the subject of his speech is an evil person and therefore it is permitted. In other cases, his evil inclination uses the opposite tactic, he will convince a person that the laws of forbidden speech are so hard to keep, that it is impossible to refrain from it, the only way being is to stop speaking altogether.
כ״ג באייר ה׳תשפ״ב
Every moment that prerson restrain him mouth he acquiting to the Hidden Light, that there is no Mal'ach and creation to be able Imagine.(Hagra letter) 1