1 John 4:3

but every spirit that does not confess Jesus is not from God, and this is the spirit of the antichrist, which you have heard is coming, and now is already in the world.

1 John 2:18

Children, it is the last hour, and just as you heard that the antichrist is coming, so now many antichrists have appeared. We know from this that it is the last hour.

1 John 2:22

Who is the liar but the person who denies that Jesus is the Christ? This one is the antichrist: the person who denies the Father and the Son.

2 John 1:7

For many deceivers have gone out into the world, people who do not confess Jesus as Christ coming in the flesh. This person is the deceiver and the antichrist!

2 Thessalonians 2:3-8

Let no one deceive you in any way. For that day will not arrive until the rebellion comes and the man of lawlessness is revealed, the son of destruction.

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
Children, it is the last hour, and just as you heard that the antichrist is coming, so now many antichrists have appeared. We know from this that it is the last hour.
2 Thessalonians 2:7
For the hidden power of lawlessness is already at work. However, the one who holds him back will do so until he is taken out of the way,
2 John 1:7
For many deceivers have gone out into the world, people who do not confess Jesus as Christ coming in the flesh. This person is the deceiver and the antichrist!

General references

Deuteronomy 18:21
Now if you say to yourselves, 'How can we tell that a message is not from the Lord?' --
John 8:47
The one who belongs to God listens and responds to God's words. You don't listen and respond, because you don't belong to God."

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