"A good tree doesn't bear bad fruit. And a bad tree doesn't bear good fruit.
You can tell each tree by the kind of fruit it bears. People do not pick figs from thorns. And they don't pick grapes from bushes.
"A good man says good things. These come from the good that is put away in his heart. An evil man says evil things. These come from the evil that is put away in his heart. Their mouths say everything that is in their hearts.