I think we are born with a carnal nature and carry this throughout our lives. I can feed my ego, choose to participate in gossip, steal from others and do numerous other things.
I believe in each second, each moment of our lives we are choosing. In this one second, one moment will I be carnal or will I be spiritual. I don't think that we can be both at the same time.
When we choose or let ourselves be carnal, we are feeding the big machine of 'self'. We may be tempted by a spirit or demon, but I'm not sure what it can exactly force us to do that we don't somehow give in to the temptation presented.
Did the television demon attach itself to me last night as I watched the Jimmy Kimmel Show? Did the demon of frustration with your teen child overcome my senses as I told my son 'no'. Does the demon of lie to your boss to get a sick day occur when it's 70 degrees and sunny? Did the demon of pharmaceuticals overtake me when I took that dose of Nyquil?
I just don't see the same possession, exorcism or deliverance things that everyone else sees. If your possessed by a demon, doesn't that demon take control over you and FORCE you to do things?
When is it a demon vs. my own carnal nature (flesh) that I've given into and sinned?