From The Abundance Of The Heart by Dr Michael H Yeager

Matthew 12:34O generation of vipers, how can ye, being evil, speak good things? for out of the abundance ( overflow) of the heart the mouth speaketh.35A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.

MSG
“You have minds like a snake pit! How do you suppose what you say is worth anything when you are so foul-minded? It’s your heart, not the dictionary, that gives meaning to your words. A good person produces good deeds and words season after season. An evil person is a blight on the orchard. Let me tell you something: Every one of these careless words is going to come back to haunt you. There will be a time of Reckoning. Words are powerful; take them seriously. Words can be your salvation. Words can also be your damnation.”