Matthew 7:15
And beware of false prophets, who come to you in sheeps clothing, but inwardly they are ravenous wolves.
2 Corinthians 11:13-15
For such are false apostles, deceitful workers, transformed into apostles of Christ.
Galatians 1:8-9
But tho' we or an angel from heaven should preach to you any other gospel than what we have preached to you; let him be accursed.
1 John 4:1
Beloved, believe not every Spirit, but try the spirits, whether they be of God: for many false prophets are gone out into the world.
Romans 1:21
so that they are inexcusable; because having thus known God they glorified Him not as God, neither were they thankful; but were infatuated by their own reasonings, and their heart being void of understanding was darkened.