Does the believer have two natures?
“Yes. Everyone born into the human race has the nature or personality they inherited from Adam.
“It is a nature that is in total rebellion to the things of God. Romans 8 calls it an enemy of God. It is subject to the ruler of this world, Satan (II Corinthians 4:4).
“Even though many good people have refined this old sin nature and kept it under control, it is still the personality that Paul describes in Romans 1 and Ephesians 2. But, that personality has to die the death of crucifixion (Galatians 2:20 and Romans 6).
Though God reckons it as dead, in our experience, he, the old Adam, is still alive and operates opposite the New Divine nature of Person, which God created in us the moment we believe the Gospel. Hence, the Christian is in a constant battle. The old nature leading us into rebellion and the new nature leading us into obedience to Christ.
The old nature can do nothing good, and the new nature cannot sin. So, which one has the upper hand in our daily life? The one we feed the best. Feed the old Adam and you will be a defeated, miserable Christian. Feed the new, or Spiritual, and you will be victorious and joyful.