How do I know?
1 John 4:1 Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world.
2 By this you know the Spirit of God: Every spirit that confesses that Jesus Christ has come in the flesh is of God,
3 and every spirit that does not confess that Jesus Christ has come in the flesh is not of God. And this is the spirit of the Antichrist, which you have heard was coming, and is now already in the world.
We are not to trust or believe things just because they sound religous. Our LORD is Jesus Christ. Everyone & everything agreeing with the word of God about Jesus, the Son of God, being God, we can agree. Many lesson the diety of Christ, making Him a mere man, or an angel. The Holy Spirit will never lead one to that. Antichrist will be recieved "instead of" Jesus, much more than be one "against" Him, though that will be a part of his plan. People who reject Jesus Christ will take anyone instead of Him. They partake of the antichrist characteristics. I choose to follow the true God, Jesus Christ, Savior, Redeemer, Healer, my all in all.