Matthew 7:15
Beware of false Teachers--men who come to you in the guise of sheep, but at heart they are ravenous wolves.
Matthew 16:6
Presently Jesus said to them: "Take care and be on your guard against the leaven of the Pharisees and Sadducees."
Matthew 16:12
Then they understood that he had told them to be on their guard, not against the leaven of bread, but against the teaching of the Pharisees and Sadducees.
Mark 4:24
Take care what you listen to," said Jesus. "The measure you mete will be meted out to you, and more will be added for you.
Mark 7:6-14
His answer was: "It was well said by Isaiah when he prophesied about you hypocrites in the words--'This is a people that honor me with their lips, While their hearts are far removed from me;
John 10:5
They will not follow a stranger, but will run away from him; because they do not know a stranger's voice."
2 Corinthians 11:13-15
Men of this stamp are false apostles, treacherous workers, disguising themselves as Apostles of Christ!
Ephesians 4:14
Then we shall no longer be like infants, tossed backward and forward, blown about by every breath of human teaching, through the trickery and the craftiness of men, towards the snares of error;
1 Timothy 4:7
As for profane legends and old wives' tales, leave them alone. Train yourself to lead a religious life;
1 Timothy 6:3-5
Any one who teaches otherwise, and refuses his assent to sound instruction--the instruction of our Lord Jesus Christ--and to the teaching of religion,
2 Peter 2:1-2
But there were false prophets also in the nation, just as there will be false teachers among you, men who will secretly introduce ruinous divisions, disowning even the Lord who bought them, and bringing speedy Ruin upon themselves.
1 John 4:1
Dear friends, do not trust every inspiration, but test each inspiration, to see whether it proceeds from God; because many false Prophets have gone out into the world.
2 John 1:10
If any one comes to you and does not bring this Teaching, do not receive him into your house or welcome him;
Revelation 2:2
I know your life, your toil and endurance, and I know that you cannot tolerate evil-doers. I know, too, how you tested those who declare that they are Apostles, though they are not, and how you proved them false.