Needing help locating a specific verse in the Bible about casting out bad influences? This might be a fool's errand, but it's my hope that someone out there more able than me will have an idea of what I'm talking about (I'm not sure my explanation is going to be very good and it will just cause headaches).

The other day, I found a verse about essentially standing up to people and/or bad influences and forcing them out of your life.  I feel like it had a lot to do with being complicit in your own misery, that evil or pain only has as much power over you as you allow it to have in your life...and I can't for the life of me find it anywhere.  I wish I had written it down.

Does anyone have any idea what I'm talking about?  Or any good leads?  I remember it being fairly short, fairly simple.  I have a suspicion it might be a Psalm or a Proverb, but I don't want to assume that and end up being way off.  Please, any help would be appreciated.  Thank you.
The advice in James 4:7 to resist the devil is sound.  But first we have to “Submit yourselves, then, to God."  We can't do it in our own strength.

Ephesians 6:12 describes the forces that believers face: 


  “For our struggle is not against flesh and blood, but against the rulers, against the powers, against the world forces of this darkness, against the spiritual forces of wickedness in the heavenly places”.


Ephesians 6:13-18 goes on to describe the spiritual armour that is necessary to overcome the forces of evil and cast out the negative influences that seek to destroy.