We could all use some work here — and I don't mean we have to be Mr. Rogers, saying only nice platitudes. I mean truth in love as well. But I have a hunch that if you're anything like me, there's some rubbish bouncing around in your skull and escaping your lips.
Paul told us to think about only good things and Jesus told us we'd be held accountable for every useless thing we say (Yikes. I'm glad He covers my sin as well).
So, give this a whirl: see if you can only say and think good stuff today (and then at the end of the day, clean up and repent!).