"Out of the same mouth proceed blessing and cursing. My brethren, these things ought not to be so." -James 3:10 (NKJV)
I think this is one of those verses that almost all of us should stop and consider in our own lives. I know I need to change how I speak and continually be aware of what I say and how I say it. Let this be a warning and a guide to all of us who want to better ourselves and follow God's word! Go and read the whole passage regarding the tongue and our words. It helped me, I hope it helps you.