Here is my understanding on the principle of Separation that was taught at the Be in Health Retreat.
The subject of Separation teaches us to separate the person from WHO is talking. A good example of this is in the Bible story about Adam and Eve. They listened to Satan and ate of the the tree of the knowledge of good and evil. Instead of listening to God and obeying Him they listened to the serpent. They then hid themselves from God because they became aware they were naked. Then God asked them “WHO told you are a naked?” They were listening to Satan instead of God.
In relating to or dealing with people, we need to be able to separate or discern WHO is talking. I find the principle of Separation as important if we are to walk in obedience to God and have good health. For self-application, if negative thoughts come upon my mind I need to ask myself WHO is behind my thoughts, Whose voice am I listening to? Most likely it is coming from Satan. As I discern it to be the case, I need to cast down those imaginations and everything that goes against the knowledge of God, and take captive every thought.
5 casting down arguments and every high thing that exalts itself against the knowledge of God, bringing every thought into captivity to the obedience of Christ,2 Corinthians 10:5
Ultimately the subject of Separation is the choice of whether to listen to and serve sin/Satan vs listen to and serve God. The more I listen to and serve God the more I will walk in health in all areas of my life.