If another believer sins against you, go privately and point out the offense. If the other person listens and confesses it, you have won that person back.
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. 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.
But who am I, and who are my people, that we could give anything to you? Everything we have has come from you, and we give you only what you first gave us!