In James 3:8, it says that the tongue cannot be tamed.—“But the tongue can no man tame; it is an unruly evil, full of deadly poison.” If you live in most normal places, you will hear many people cursing. Some people don’t have the guts to speak up. You know you really should.
Don’t you want to see your friends in heaven? I do. There are many ways to tell those that use vulgar language to not use that language. What I usually say is, “Please stop using that language. It’s bad.”´ Sometimes my example helps, but sometimes not. Sometimes you just have to keep trying.
1 Timothy 4:12 admonishes us to “Let no man despise thy youth; but be thou an example of the believers, in word, in conversation, in charity, in spirit, in faith, in purity.” [Emphasis supplied.]