Christians are, at times, too quick to cast out demons. They must first manifest themselves. This article explains the reason why.
In the beginning, God created man to have dominion over the entire Earth (Genesis 1:28). At this point, man’s decisions would not be interfered with by God. The Lord gave man the power to name the world’s beasts (Genesis 2:19); whatever Adam called them, it was final. The naming of the beasts was an exercise in the gift of dominion that God has given humanity.
Satan may be many bad things, but he is also a brilliant tactician. Satan waited to tempt Eve & Adam AFTER they had disobeyed God. The reason: anything that the first man and woman would do could not be revoked by God, even if their actions went against the Lord’s Will. God cannot take back what He has given (Romans 11:29).
Because of Satan’s strategy, humanity would be a proxy for him and other fallen angels (demons/unclean spirits) to defy God. While the unclean spirit(s) hide behind humanity’s free will, they are immune to being cast out/off of any individual. Demons are resistant because they are not deciding to sin, only influencing. To a believer wanting to deliver their friend or family member from torment, this can be a frustrating time, but there is a solution.
So, how do I know when to cast out a demon in Jesus’ Name? Easy, wait until they manifest themselves.
In all four Gospels and the book of Acts, demons weren’t cast out until their character traits (manifestations) occurred. When people were deaf & dumb (Mark 9:25, Matthew 12:22), sickness/weakness (Luke 4:38-41), erratic behavior (Mark 5:1-10), and other external signs appeared, only then did Jesus & His follower’s act. When demons show their face through these manifestations, as found in the Gospels & Acts, it’s time to cast them out.
I will add an addendum. Demons can be cast out of someone who has genuinely repented of their sins and knows there’s a problem with unclean spirits. This act removes the foothold (Ephesians 4:27) a demon(s) has over a person.
Now, we must keep in mind that demons CAN INFLUENCE carnal behavior. Examples of the flesh can be found in Galatians 5:19-21. When a Christian encounters an individual with no visible manifestations, only carnal behavior, casting them out won’t work because they’re “hiding” behind the will & decisions of the individual. God will not go against the choices of anyone as each person has free will, even to disobey.
So, what can you do?
Nothing until they (demons) show their face. I’ve seen many Christians try to provoke them to the surface, but unless you know what you’re doing, this can be a risky effort.
You address the carnal behavior differently depending on who you are talking to. To the lost, you preach the Gospel and hopefully lead them to Jesus. To Christians, you show them scripture, which might provoke unclean spirits to the surface. Asking God for wisdom is vital, as well as understanding your authority.