Matthew 12:33-35

33Then Jesus said, ‘To have good fruit you must have a good tree. If you have a bad tree, then you will get bad fruit from it. You can know all about a tree by the kind of fruit that it makes.

34You are like the children of dangerous snakes. You cannot say good things when your thoughts are bad. When you speak, your words show what is in your mind.

35It is like things that you bring out of a room where you keep them. The good man says good things because he keeps good thoughts in his mind. The bad man says bad things because he keeps bad thoughts in his mind.