Matthew 7:15
"Look out for deceiving prophets, who approach you wearing sheep's clothing, but who are [actually] starving wolves in their hearts.
Romans 16:18
For such men are not serving our Lord Christ but their own [unspiritual] appetites. They are deceiving the minds of innocent people by their smooth talk and flattering words.
Acts 20:29-30
[Because] I know that after I am gone [from here] there will be vicious wolves [i.e., ravaging false teachers] who will come in among you, and they will not spare the flock [i.e., the congregation].
2 Corinthians 11:13-15
For such men are false apostles; they are deceitful workers, who disguise themselves as [true] apostles of Christ.
Galatians 2:4
For [certain] false brothers, who were secretly brought in to observe us practicing our liberty in Christ Jesus [i.e., by not having Titus circumcised], attempted to place us [back] under the bondage [of Mosaic law keeping].
1 Timothy 4:1-2
Now the Holy Spirit specifically says that in later times [Note: "Later times" in the New Testament usually refers to the period following the first coming of Christ and the establishment of the church], some people will fall away from the faith [i.e., the true teaching of Christianity]. They will pay attention to deceitful spirits [i.e., lying people] and the teaching of evil spirits.
2 Timothy 3:1-7
But you should know this: There will be terrible times in the last days [of the Christian age].
2 Timothy 4:3
For the time will come when people will not tolerate sound teaching, but will assemble to themselves teachers who will satisfy what their "itching ears" want to hear.
Titus 1:11
They must be silenced [because] they are upsetting entire families by teaching things they should not be for the shameful purpose of making money.
2 Peter 2:1-3
But just as there were false prophets among the people before, there will also be false teachers among you [Christians]. They will privately teach harmful doctrines that destroy people [spiritually], by even denying [that Jesus is] the Master, [and thereby] destroying themselves quickly.
2 Peter 2:18-19
[Although] their talk is big, what they say is worthless, and by [offering people] fleshly desires [i.e., sexual gratification], they lead people astray, who are barely escaping from the error of the world.
1 John 2:18-19
Dear children, it is [now] the last hour [i.e., the final period of God's dealing with people on earth], and since you have heard that an antichrist [i.e., a person who is against Christ] is coming, even now [you should be aware that] many antichrists have [already] come. This is [one way] we know that this is the last hour.
1 John 4:1
Loved ones, do not believe [the message of] every spirit [i.e., every person claiming to be a teacher], but test the spirits [i.e., require proof that they and their message are genuine] to see whether they represent God [or not], because many false prophets have begun circulating throughout the world.
1 John 4:5
These [false teachers] are part of the world, so [naturally] they speak [a message endorsed] by the world and the world listens to them.
2 John 1:7
For many deceivers have begun circulating in the world; they are those who do not confess that Jesus Christ has come [to earth] in a physical body. Such a person is the deceiver and the antichrist [See I John 2:18f].
Jude 1:4
For certain men have secretly infiltrated [your ranks]; they are men who had been written about long ago that they should be judged [and condemned] for perverting the unearned favor of our God into [a license for] living unrestrained, indecent lives, and who deny [the identity and work of] our only Master and Lord, Jesus Christ.
Revelation 2:20
But I have this against you, that you tolerate that woman [named] Jezebel, who calls herself a prophetess. She teaches and deceives my servants into [practicing] sexual immorality and into eating things sacrificed to idols.
Revelation 12:2-6
She was pregnant, and cried out in pain as she was about to give birth.
Revelation 12:13-4
And when the dragon saw that he had been thrown down to earth, he persecuted the woman who had given birth to a son.
Revelation 13:11-14
Then I saw another [i.e., a second] beast coming up from the earth. He had two horns like a lamb and spoke like a dragon.