Here "flattering lips" is a metonym for people who flatter others. Possible meanings are 1) "cut off" is a metaphor for killing. Alternate translation: "kill all who flatter others" or 2) "cut off" is a metaphor for stopping something. Alternate translation: "stop all those who flatter others" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-metonymy]])
Here "every tongue" represents every person who declares great things. Alternate translation: "every person who boasts" (See: [[rc://en/ta/man/translate/figs-synecdoche]])