In the parable of the sower, Jesus said that the birds that took away the seed represented the evil one. So demons, unclean spirits and birds all have the same meaning. Babylon is full of these evil things. In recent years there has been a revived interest in exorcism. Many people have genuinely been delivered from evil, but others have failed to understand the real problems.
Evil spirits are at home where there is sin.
Demon possession and demonic influence are not the same as sin, but are closely linked with it. The heathen world deals with demons by ceremonies and incantations and magic words. Moral values do not matter. Sin is irrelevant. It is a matter of manipulating or appeasing spirits.