>>850215
19 They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.
Pretty clear on it's own
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.
>if it were possible
That means it isn't. If the anti-christ and false prophet can't even decieve the elect, I hightly doubt some other false teacher can