4 Dear friends, do not believe everyone who claims to speak by the Spirit. You must test them to see if the spirit they have comes from God. For there are many false prophets in the world. 2 This is how we know if they have the Spirit of God: If a person claiming to be a prophet acknowledges that Jesus Christ came in a real body, that person has the Spirit of God. 3 But if someone claims to be a prophet and does not acknowledge the truth about Jesus, that person is not from God. Such a person has the spirit of the Antichrist, which you heard is coming into the world and indeed is already here.
4 But you belong to God, my dear children. You have already won a victory over those people, because the Spirit who lives in you is greater than the spirit who lives in the world. 5 Those people belong to this world, so they speak from the world’s viewpoint, and the world listens to them. 6 But we belong to God, and those who know God listen to us. If they do not belong to God, they do not listen to us. That is how we know if someone has the Spirit of truth or the spirit of deception.
1 John 4:1-6 (NLT)