1 John 4:1
Beloved, do not believe every spirit, but try the spirits, whether they be from God; because many false prophets are gone forth into the world.
2 Peter 2:1
But there were also false prophets among the people, even as there will be false teachers among you; who will privately introduce destructive sects, denying even the Lord who bought them, bringing on themselves swift destruction.
1 John 2:18
Young children, it is the last period. And as you have heard that the antichrist comes, so, now, there are many antichrists; whence you know that it is the last period.
2 John 1:7
for many deceivers are entered into the world, who do not confess Jesus Christ did come in the flesh. This is the deceiver, and the antichrist.
Revelation 2:2
I know your works, and your labor, and your patience; and that you can not bear those who are evil: and you have tried those who say they are Apostles, and are not, and have found them liars;