Replies

2 Peter 2
1 But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction.

2 And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of.
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20 For if after they have escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, they are again entangled therein, and overcome, the latter end is worse with them than the beginning.

21 For it had been better for them not to have known the way of righteousness, than, after they have known it, to turn from the holy commandment delivered unto them.

22 But it is happened unto them according to the true proverb, The dog is turned to his own vomit again; and the sow that was washed to her wallowing in the mire.

But the elect cannot be deceived (notice the subjunctive case):

Matthew 24:24
For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect.

Mark 13:22
For false Christs and false prophets shall rise, and shall shew signs and wonders, to seduce, if it were possible, even the elect.