This song is obviously about shallow, annoying shittalkers who have nothing better to do than to point out what's wrong with other people. "Your tongue bores me numb" meaning they are tired of the meaningless things that people say to critisize others, "shallow opinion" is self-explanatory, and then "clean out the poison when you cut out your tongue" pretty much means that they should change their ways and quit forming useless opinions and making negative statements about other people.
This song is obviously about shallow, annoying shittalkers who have nothing better to do than to point out what's wrong with other people. "Your tongue bores me numb" meaning they are tired of the meaningless things that people say to critisize others, "shallow opinion" is self-explanatory, and then "clean out the poison when you cut out your tongue" pretty much means that they should change their ways and quit forming useless opinions and making negative statements about other people.