“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.” (Romans 6:19, ESV)
There are a variety of old expressions that describe behaviors and their results, like these. You are what you eat! It doesn’t mean that if you eat donuts all the time that you are a donut, but that this type of steady diet will greatly affect your health and appearance. You get what you pay for! This means that if you go cheap, expect a cheap product. I would like to add a similar saying. What you seek changes you!
Paul here speaks of this by comparing the person who is a slave to impurity and lawlessness to the person who is a slave to righteousness. In both cases the person is seeking something based upon his or her condition. As mentioned before, the person who is a slave to sin has an inner desire for sin. Conversely, the person who is a slave to righteousness has an inner desire for righteousness. Paul now explains that in their seeking, there are repercussions. What you seek changes you!
Formerly, we were slaves to sin and being weak in the flesh, presented our bodies as slaves to impurity and lawlessness. This pursuit increased lawlessness in our lives as our sins compounded and multiplied.
In the same way, now that we are under grace, we are to present our bodies to righteousness. This will result in sanctification. Sanctification is the process initiated by the Holy Spirit’s work of regeneration and carried on by the work of the Holy Spirit in which the believer is progressively made holy.
While sanctification is a work of God’s grace wrought by the Spirit, the believer has the responsibility in yielding to this work. When the believer yields, presenting his body to righteousness, the result will be sanctification, where the believer will be more and more separated from sin and set apart for the glory of God.