"Beware of false prophets, who come to you in sheep's clothing, but inwardly they are ravenous wolves.
Matthew 7:15
Surrounding context
7:14 Because narrow is the gate and difficult is the way which leads to life, and there are few who find it.
7:15 "Beware of false prophets, who come to you in sheep's clothing, but inwardly they are ravenous wolves.
7:16 You will know them by their fruits. Do men gather grapes from thornbushes or figs from thistles?