Proverbs 15:4 amp

A gentle tongue (with its healing power) is a tree of life, but willful contrariness in it breaks down the spirit.  

The words we speak are like the keys to a treasure chest.  We have the power to proclaim our chest full or empty by the words we speak.  When we are full of the word of God, the creative force will come through our hearts and are spoken out of our mouths.