What does Satan want to accomplish through the old nature?
Satan works through the old nature as his playground, seeking to get the old Adamic nature to control and to exercise its desires. His aim is to fulfill his own desire by getting the old nature to dominate and act out those desires.
Les teaches that while people often say “the devil made me do it,” that is not very often the case; old Adam is the one who makes us do it. But Satan is not left out of the picture. Satan works through the old nature, which is his playground. That is where he loves to fulfill his desire: by getting our old Adamic nature to control and to exercise the desires of the old nature. The comfort for the believer is that He who is within you is greater than the powers of Satan.