2 John 1:7
“For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.”
And now I beseech thee, lady, not as though I wrote a new commandment unto thee, but that which we had from the beginning, that we love one another.
And this is love, that we walk after his commandments. This is the commandment, That, as ye have heard from the beginning, ye should walk in it.
For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.
Look to yourselves, that we lose not those things which we have wrought, but that we receive a full reward.
Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son.
Why This Verse Was Tagged
This verse contains specific terms directly associated with this theme.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.”
“Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son.”
“Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time.”
“That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.”
“And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth.”