Words can do a lot of good and a lot of harm. That's why you have to be so careful with them. The problem is that, once you think the words, they start stomping and snorting and pushing against the starting gate, trying to get out. If they're business-meeting words or an over-the-back-fence words, they usually don't push too hard. The words that give you the most trouble are the ones you're dying to say to the folks you know best, which is just where they can do the most good and the most harm. That's why you have to be really strict with them, especially when it would be so much easier just to open the gate. 

"Because I think them." Howard Stern, when somebody asked him why he says things

"A word aptly spoken is like apples of gold in settings of silver." Prov. 35:11