I will have to start at the deginning. God created the angels like the military but instead of rank God gave them power and authority from the least in power and authority up to and including God's generals or archangels. When 1/3 of the angels rebelled one thing He did was to take their bodies from them making them spirit beings only. (some have different bodies and are posing as aliens and some have taken over our underground bases and are making bodies and walk among us) The 1/3 of fallen angels came into our hearts and became the inborn nature. They do not have the power to possess as in demonic possession but they do controll us. It takes several of the least in power and authorithy or one of a higher power to possess us as in demonic possession. They raise up emotions and desires, give us feelings, urges, and impressions, and they put thoughts into our mind and words into our mouth especially when we give into an emotion like anger. When God's Spirit comes into our heart He casts out this inborn nature and with it goes these bad emotions because God will not dwell where sin dwells. Now we can say no to sin and ignor emotions. Buy if you give into an emotion and sin you must repent and ask God to cleanse your heart again. But be careful God will leave your heart and allow the inborn nature back in and if that happens it will take 7 demons worse than itself and come back in. Sex outside marriage, illegal drug use and demon worship are a few of the things God will not tolerate.