1 John 4:3

while all inspiration that does not acknowledge Jesus is not inspiration from God. It is the inspiration of the Anti-Christ; you have heard that it was to come, and it is now already in the world.

1 John 2:18

My Children, these are the last days. You were told that an Anti-Christ was coming; and many Anti-Christ's have already arisen. By that we know that these are the last days.

1 John 2:22

Who is a liar, if not the man who rejects the truth that Jesus is the Christ? He is the Anti-Christ--The man who rejects the Father and the Son.

2 John 1:7

I say this because many impostors have left us to go into the world--men who do not acknowledge Jesus as Christ come in our human nature. It is that which marks a man as an impostor and an anti-Christ.

2 Thessalonians 2:3-8

Do not let any one deceive you, whatever he may do. For it will not come until after the Great Apostasy, and the appearing of that Incarnation of Wickedness, that the Lost soul,

Treasury of Scripture Knowledge

Summary

And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world.

General references

Bible References

And this

1 John 2:18
My Children, these are the last days. You were told that an Anti-Christ was coming; and many Anti-Christ's have already arisen. By that we know that these are the last days.
2 Thessalonians 2:7
Wickedness, indeed, is already at work in secret; but only until he who at present restrains it is removed out of the way.
2 John 1:7
I say this because many impostors have left us to go into the world--men who do not acknowledge Jesus as Christ come in our human nature. It is that which marks a man as an impostor and an anti-Christ.

General references

John 8:47
He who comes from God listens to God's teaching; the reason why you do not listen is because you do not come from God."