2 Corinthians 11:13-15
For such are fake apostles, deceitful labourers, transforming themselves into apostles of Christ.
Matthew 7:15
Take heed then of false prophets, who come to you in the garb of sheep, but inwardly they are ravening wolves.
Philippians 3:2
Beware of dogs, beware of the malicious labourers, beware of the concision.
2 Peter 2:1-3
BUT there were false prophets among the people, as there will be false teachers also among you, who wickedly introduce damnable heresies, and deny the sovereign Lord who bought them, bringing on themselves swift destruction.
1 John 4:1
BELOVED, believe not every pretender to inspiration, but bring these spirits to the trial whether they are of God; because many false prophets are gone forth into the world.