Romans 6:19 I am speaking in human terms, because of your natural limitations. For just as you once presented your members as slaves to impurity and to lawlessness leading to more lawlessness, so now present your members as slaves to righteousness leading to sanctification.
Paul is emphatically stating that unregenerate sinners are not unwilling slaves to sin, but are more than willing to present their members to the slavery of lawlessness. As such the unregenerate are dead in sin and have no freedom or ability to refrain from presenting their members to impurity and sin. But now Paul is exhorting those who have been set free from sin by the power of God to present their members as slaves to righteousness. Having been set free from the slavery of sin, believers have the freedom and power to pursue righteousness, and Paul completely rejects any possibility of a Christian having two masters. While Christians still sin, they no longer willingly, regularly, and without remorse present themselves to lawlessness and impurity. There are no carnal or nominal Christians! A person is either a regenerated disciple of Christ being led by the Spirit of God or he is not a Christian at all. The fruits of sanctification flow from the internal Spirit caused desires of the new covenant and not from the external legalistic performance based old covenant.
Focus on Christ #133