God speaks of a person speaking evil things as if that person's mouth is a messenger whom the person sends to do evil things. Alternate translation: "You are always saying evil things" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-synecdoche]])
The word "tongue" represents the person who is speaking. Alternate translation: "you are always telling lies" (See: [[rc://en/ta/man/translate/figs-synecdoche]])