2 Corinthians 11:13-15
For such false apostles, deceitful laborers, transform themselves into apostles of Christ.
Matthew 7:15
But beware of false prophets, who come to you in sheep's clothing, but within they are rapacious wolves.
Philippians 3:2
Beware of the dogs, beware of evil laborers, beware of the concision.
2 Peter 2:1-3
But there were also false prophets among the people, as there shall also be false teachers among you, who shall bring in by stealth destructive heresies, even denying the master that bought them, bringing on themselves swift destruction;
1 John 4:1
BELOVED, believe not every spirit, but prove the spirits whether they are of God; for many false prophets have gone out into the world.