Matthew 7:16-20

Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles?

Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit.

A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit.

Every tree that bringeth not forth good fruit is hewn down, and cast into the fire.

Wherefore by their fruits ye shall know them.