In response to what you wrote in ‘Satan in our minds’, I was wondering how Satan has access to our thoughts and deeds if he isn’t omniscient or omnipresent.
In following on from this thought, I have also begun to wonder whether Satan is allowed by God, to be physically in the presence of believers – or whether having ‘Christ within’ prevents him from doing so.
He doesn’t have to be omni present or omniscient. He has a huge demonic following to help him, and just has to influence your thinking by suggesting things to you.
I don’t think that believers can be demon possessed, but I know they can suffer demonic oppression. When James 4:7 says “resist the devil and he’ll flee from you”, it implies that he or one of his helpers can be in your presence and tormenting you. Submitting ourselves to God in the same verse means to admit we’re sinners and confess so we can be restored to fellowship and God’s protection. Verse 8 confirms this.
Submit yourselves, then, to God. Resist the devil, and he will flee from you. Come near to God and he will come near to you. Wash your hands, you sinners, and purify your hearts, you double-minded. (James 4:7-8)