Luke 6:43-45

43 "For no good tree produces bad fruit, nor does a bad tree produce good fruit.

44 Each tree is recognized by its own fruit -- figs aren't picked from thorn bushes, nor grapes from a briar patch.

45 The good person produces good things from the store of good in his heart, while the evil person produces evil things from the store of evil in his heart. For his mouth speaks what overflows from his heart.