Often, people are confronted by demonic forces and don't even realize
that it's happening.  I'm often amazed at the inability of the average
Christian to detect and confront demonic forces .  It's really very
simple to confront the enemy when it's just everyday stuff.  Basically,
and this will take time and patience; you simply return the opposite
spirit against the enemy force confronting you.  For example, if you are
being confronted by the presence of fear, use a spirit of boldness, a
spirit of lies, use a spirit of truth, a spirit of lust, use a spirit of
Holiness.  You see all of the weapons we use to fight and confront
everyday enemy forces come from the One and the same Holy Spirit of God.

But, what happens when you are in a ministry situation and a demon
actually, manifest on a person?  Well, first understand that unless the
person wants the demonic force in their life to leave and wants to
replace the freshly swept room with the Holy Spirits' presence, it's best
to leave it alone.  If you kick out the demon and the person doesn't want
to fill that new empty space with God, the demon can come back with
friends and the person would be worse off than before.   You can easily
find out just by asking the person if that's what they want.  If the
demon is manifesting so powerfully, the person can't comprehend or answer
your question, you can just tell it to shut up and allow the person to
speak. I can tell you this because I've been involved in deliverance
ministry personally, and I've had some experience.  I do believe that
born again believers can have demonic influence in their lives which can
plague them and they need deliverance as well as an unbeliever would.  I
however, do no not believe in using the word possession.  The reason is
because the very word connotates total control.  I've never once heard of
or ever seen anyone under total control of the enemy.  That really does
not seem scriptural either because then the person would not be able to
call out for God's help and we can always call out to Him for our
Salvation and deliverance. 

You see, we have to understand how much authority we really do have in
Christ.  It's very important that we do not give in to fear tactics when
confronting or being confronted by demonic forces.  Understand that in
America we have the Hollywood syndrome, we are accustomed to seeing
demons on the TV or Big Screen as bigger and stronger than we are, and
even able to do us harm.  When in fact the very opposite is true, and
demons realize this as well.  They put on these Grand theatrics such as
making the bed shake or contorting their host persons' face, and even
speaking with their own voice through that person.  But, the real and
true reality is that if we are found in Christ, the demons are powerless
against us, including that we are not wallowing in unrepentant sin.  If
we as Christians have unrepentant sin in our lives the rules change
because we have given the enemy ground to stand on. 

Always remember to seek God for instruction during the deliverance, you
might be surprised at what works to make a demon go when they are being
stubborn and you've tried every example in the Bible and nothing seems to
be working.  So, the first rule is to repent completely before directly
confronting demonic forces so that they become powerless to harm you.
Beyond that we have full authority in Jesus to take ground away from them
and command them to go away.  I have been involved in demonic deliverance
where the demon was simply commanded to stop the theatrics when he begin
to put on a little Hollywood horror show and he did and left.  The
theatrics couldn't hurt anyone anyway and only served to distract the
person taking authority over him.

If you've never seen a demon and don't believe they exist, let me say
that you would only have to see a demon manifest one time and you would
never doubt their existence again.  Furthermore, to say that demons are
not real is to call the Bible false. Finally, some people believe in the existence 
of such forces and don't even personally know Christ themselves.  I urge you, 
do not mess with a demon unless you have personally received Jesus as your savior.  Check out in the Bible what can happen if you try it.   Acts Chapter 19.

Blessings,
Dennis