It is worth noting who talks about the antichrist in the New Testament. The very one who argues that Jesus is YHWH God the Creator and not an Angel (John 1:1). To John, the Deceiver and the Antichrist is the same (2 John 1:7). In Revelation 12:9, He identifies the Deceiver as Satan and Devil and Dragon and Old Serpent. So, Satan is known as the Old Serpent, the Dragon, the Devil, the Antichrist, the Deceiver of the whole world.
When we act, we do so under one of the two influences: the spirit of Satan or the Spirit of God. We can do both good and evil deeds.
God wants us to be perfect in doing good all the times. He is ready to forgive us whenever we become cognizant of our sins and ask for forgiveness and abandon our sins (1 John 2:1). God does not allow us to carry on with even one sin (James 2:10).
Because Satan knows that God requires absolute obedience (James 2:10), Satan does not mind our imperfection. He will brandish the case of Adam and Eve to show that no matter how perfect God makes us, we still can fail, even if he has to go through deceptive tactics of misrepresentations to get us to fall (2 Corinthians 11:13-15).
God the Father counters Satan by sending YHWH God (John 3:16, Luke 2:11, Titus 2:13. Psalms 23:1, John 10:16, 27), with whom we share the same genes (Genesis 1:26, Psalms 82:6, John 10:34-36) to show that, yes, we can be perfect as long as we do not deviate from the will of God (Deuteronomy 4:, 5:32, Matthew 5:17-18, Mark 7:7).
The Jesus birthers are also antichrists (Romans 10:9-11).
1 John 2:18 LITV
Little children, it is a last hour, and as you heard that the antichrist is coming, even now many antichrists have risen up, from which you know that it is a last hour.
1 John 2:22 LITV
Who is the liar, except the one denying, saying that Jesus is not the Christ? This is the antichrist, the one denying the Father and the Son.
1 John 4:3 LITV
And every spirit which does not confess that Jesus Christ has come in the flesh is not from God; and this is the antichrist which you heard is coming, and now is already in the world.
2 John 1:7 LITV
Because many deceivers went out into the world, those not confessing Jesus Christ to have come in the flesh, this is the deceiver and the antichrist.
Revelation 12:9 ASV
And the great dragon was cast down, the old serpent, he that is called the Devil and Satan, the deceiver of the whole world; he was cast down to the earth, and his angels were cast down with him.