Matthew 7:15
Beware of the false prophets, who come to you in sheeps clothing, but inwardly are ravening wolves.
2 Corinthians 11:13-15
For such are false apostles, deceitful workmen, transforming themselves into apostles of Christ.
Galatians 1:8-9
But even if we or an angel from heaven should preach a gospel to you contrary to that which we preached to you, let him be accursed!
1 John 4:1
Beloved, believe not every spirit, but try the spirits, whether they are of God; because many false prophets have gone forth into the world.
Romans 1:21
Because though they knew God, they did not glorify him as God, nor were they thankful to him; but became perverse in their reasonings, and their senseless minds were darkened;