"Behold, we put bits in the horses' mouths, that they may obey us; and we turn about their whole body. Behold also the ships, which though they be so great, and are driven of fierce winds, yet are they turned about with a very small helm, whithersoever the governor listeth. Even so the tongue is a little member, and boasteth great things. Behold, how great a matter a little fire kindleth!"
-- James 3:3-5
How many times do we say things we don't really mean and think nothing of it? If anyone comments, or if we have a little twinge of Spirit-conscience, we immediately follow up with "just kidding"!
As children we used to say "Sticks and stones may break my bones, but words can never hurt me". Apparently, James disagrees.