Also: By their fruits you shall know them.
Matthew 7:17-19
Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. [18] A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit. [19] Every tree that bringeth not forth good fruit is hewn down, and cast into the fire.
Matthew 12:33
Either make the tree good, and his fruit good; or else make the tree corrupt, and his fruit corrupt: for the tree is known by his fruit.
Luke 3:9
And now also the axe is laid unto the root of the trees: every tree therefore which bringeth not forth good fruit is hewn down, and cast into the fire.
Luke 6:43-44
For a good tree bringeth not forth corrupt fruit; neither doth a corrupt tree bring forth good fruit. [44] For every tree is known by his own fruit. For of thorns men do not gather figs, nor of a bramble bush gather they grapes.