Use your words. But oh so carefully.

Be careful with your words.  Once they are said, they can only be forgiven, not forgotten.  Unknown

The tongue is one of the sharpest weapons we each possess.  It wields great power that brings life or death to the hearer.  (Read this for more about the tongue.)
Our tongues deliver words but the words are born in our hearts.  One might argue with me and say they come from the mind but our minds and tongues are only a delivery system of our hearts.  Click here.  :) 
So, yes, be careful with your words.  Before you speak them, think about them, and then you may need to examine your heart.  It's always wise to put ourselves in the place of others.  Think about the last time someone said something sharp and wounding to you.  Hopefully you've been able to forgive them and their careless words but I'm betting you haven't forgotten them.  I'm guessing that from time to time they echo in your head and heart and you have to do some work to put those hurtful words back in their proper place.  So remember how you feel with those words and the next time you are about to speak and hesitate listen to the hesitation and consider how you want to wield your weapon in the life of another.