Matthew 7:15-20
15 ‘Beware of false prophets who come to you disguised as sheep but underneath are ravenous wolves.
16 You will be able to tell them by their fruits. Can people pick grapes from thorns, or figs from thistles?
17 In the same way, a sound tree produces good fruit but a rotten tree bad fruit.
18 A sound tree cannot bear bad fruit, nor a rotten tree bear good fruit.
19 Any tree that does not produce good fruit is cut down and thrown on the fire.
20 I repeat, you will be able to tell them by their fruits.