What does Romans 6 teach about the old Adam?
Romans 6 teaches that the old Adam is the old sin nature, a mortal enemy to be reckoned crucified with Christ and put to death constantly. Though God reckons it dead at salvation, in experience it remains, plagues believers, until leaving the mortal body.
Les explains that the question of two natures for the believer is answered absolutely: believers still have the old nature, the old Adam that constantly pursues them, and they also have the new nature as a result of salvation and union with Christ. This is a Pauline doctrine of continual warfare between the old sin nature and the new divine nature. In dying daily, the believer must keep old Adam in subjection and put him to death. Les points to Romans 6:13 and the whole sixth chapter of Romans, where Paul deals with reckoning old Adam as our mortal enemy and constantly putting him to death. God, in His omnipotence and sovereignty, reckoned our old Adam as crucified with Christ the moment we believe, so he is dead; but in experience he is still with us, and he plagues us until we leave this body of mortality.
Neither yield ye your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God.