The question of whether Christians can be demon possessed is both controversial and complex.The issues involved include the nature of possession, the possibility of demonic deceivers, thefact of two spiritual kingdoms, the fact that Christians are sealed by the Holy Spirit, the activitiesof Satan and demons, the possibility of wolvesappearing in sheep’s clothing, the difficulty ofdiscerning tares and wheat, the possibility ofgrieving and quenching the Holy Spirit, theproblem of Christians walking after the flesh,and the complicating roles of the world and theflesh. As whole beings, spiritual and psychological factors interact; assessment and interventionmust reflect this. Suggested strategies include spiritual disciplines, practical spiritual equipping,and counseling or psychotherapy; ideally theseare carried out by a teamof helpers who worktogether effectively and conceptualize the problem wholistically.
Bufford, Rodger K., "Demonic Influence and the Christian: Issues and Implications for Counseling" (2008). Faculty Publications - Grad School of Clinical Psychology. 40.