Dear Catholic Exchange,
One very obvious passage that could have been included in your article "Is Using Foul Language a Sin?" is Colossians 3:8: "But now you must put them all away: anger, fury, malice, slander, and obscene language out of your mouths." This is from the NAB translation.
God bless you for your work,
Fr. John Lankeit
St. Anne Catholic Church
Thank you for your constructive criticism (really, for your attentiveness). I've copied your suggestion to our database to be incorporated on next use.
Please mention us in your prayers.
United in the Faith,