Matthew 7:15-18 NIV

[15] “Watch out for false prophets. They come to you in sheep’s clothing, but inwardly they are ferocious wolves. [16] By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles? [17] Likewise, every good tree bears good fruit, but a bad tree bears bad fruit. [18] A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit.