Jesus talks about the lost sheep, and leaving the flock to go gather the lost sheep back into the fold. This is your spirit filled believer that goes astray, and they do sometime go astray. He said that he would lose none that are his,even if it means taking them before their time to keep them from losing their soul. The other believer is the one that turns back ,like a dog that turns and eats it's own vomit. that is because they had not been spirit filled,although cleansed of their sins, but no holy spirit. demons move back in because the house is empty, and bring seven more worse than he.