Matthew 7:16-19
7:16 You will recognize them by their fruit. Grapes are not gathered from thorns or figs from thistles, are they?
7:17 In the same way, every good tree bears good fruit, but the bad tree bears bad fruit.
7:18 A good tree is not able to bear bad fruit, nor a bad tree to bear good fruit.
7:19 Every tree that does not bear good fruit is cut down and thrown into the fire.