8.16-Be alert to false teachers.

8.16-

Do not be naive.  There are false teachers.  They will do "miracles" "signs and wonders". There are people who promise freedom and give captivity.

Mark 13.
²² for false Christs and false prophets will arise, and will show ^[l]signs and wonders, in order to lead astray, if possible, the elect.

Matthew 7.
¹⁵ “Beware of the false prophets, who come to you in sheep’s clothing, but inwardly are ravenous wolves. ¹⁶ You will ^[k]know them by their fruits. ^[l]Grapes are not gathered from thorn bushes nor figs from thistles, are they? ¹⁷ So every good tree bears good fruit, but the bad tree bears bad fruit. ¹⁸ A good tree cannot produce bad fruit, nor can a bad tree produce good fruit. ¹⁹ Every tree that does not bear good fruit is cut down and thrown into the fire. ²⁰ So then, you will ^[m]know them by their fruits.

1 John 4.
4 Beloved, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world.  

2 Peter 

2 But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves. ² Many will follow their sensuality, and because of them the way of the truth will be maligned; ³ and in their greed they will exploit you with false words; their judgment from long ago is not idle, and their destruction is not asleep.