No where in the Bible does it say if one does not believe God Sacrificed Jesus Christ for the sins of mankind, he or she is the anti-christ or satanic."
2 John 1:7
7For 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.
No one here is denying the existance of Jesus. We simply don't believe there is a god, and therefore, Jesus was simply a human being, like you and me.