They will inevitabley be messed up in one of these area:
1. Jesus is the Son of God and Christ.
2. They will deny in some way the fact that Jesus came in the flesh and rose from the dead.
3. They will have difficulty confessing Jesus is their Lord.
Overall they will have trouble with the gospel. When pressed, an evil spirit will curse Jesus, refuse that He is their Lord, and become very agitated when you talk about the blood of Jesus.