So let’s begin with Jesus. Matthew 7:15: “Beware of false prophets, who come to you in sheep’s clothing but inwardly are ravenous wolves.” And the word beware means all of us should be alert, but especially shepherds, to identify not just false teaching, but false teachers, whose ways are subtle. They’re clothing themselves with lamb’s wool while they’re wolves.
And Paul used the same Greek word for beware in Acts 20:28–29 when he said, “Pay careful attention to yourselves and to all the flock, in which the Holy Spirit has made you overseers. . . . I know that after my departure fierce wolves will come in among you, not sparing the.”
“In order to protect the flock, we should expose false teachers and minimize the spread of the gangrene.”
Jesus used the same word again in Matthew 16:6, but he got more specific: “Watch and beware of the leaven of the Pharisees and Sadducees.” Paul had the same kind of group in mind and the same kind of error in mind in Philippians 3:2 and 3:18: “Look out for the dogs, look out for the evildoers, look out for those who mutilate the flesh.” And then verse 18: “For many, of whom I have often told you and now tell you even with tears, walk as enemies of the cross of Christ.” Then in Romans 16:17, he warned, “Watch out for those who cause divisions and create obstacles contrary to the doctrine that you have been taught; avoid them.”