There is a great difference between power and authority.  The average Christian doesn't understand the difference.  Authority is the right to use power. We only have access to authority when we are under that authority.  James said that we could only resist the devil after we had submitted ourselves to God. Until we are submitted to God, we don't have His authority flowing through us.  

If you have tried to resist Satan in an area of your life unsuccessfully, it is probably because you are not submitted in that area.  You can experience consistent financial blessing by using these principles.

But the good news is that they will not only work in the area of finances, but in any area of your life.