Romans 6:12-18 (Quoted from NLT)

12-14 “Do not let sin control the way you live.  Do not give in to sinful desires. (13) Do not let any part of your body become an instrument of evil to serve sin. Instead, give yourselves completely to God, for you were dead, but now you have new life.  So use your whole body your whole body as an instrument to do what is right for the glory of God.  (14) Sin is no longer your master, for you no longer live under the requirements of the law.  Instead you live under the freedom of God’s grace.”

15-18 “Well then, since God’s grace set us free from the law, the does that mean we can go on sinning?  Of course not! (16) Don’t you realize that you become the slave of whatever you choose to obey?  You can be a slave to sin, which leads to death, or you can choose to obey God, which leads to righteous living.  (17) Thank God! Once you were slaves of sin, but now you whole heartedly obey his teaching we have given you. (18) Now you are free from your slavery to sin, and you have become slaves to righteous living.” 

My comments:  Our spirits used to be dead, but when we accepted Christ they came to life, and because we have become new people, we shouldn’t let sin control us anymore.  We should have a new desire to please God, and we should use our bodies as instruments to glorify Him.  We are no longer under the requirements of the Old Testament Law, now we are under grace.  Which does not mean that we have the freedom to sin, but it does mean that we can now choose who we obey. If we obey our sinful desires, then that will eventually lead to death, because all sin is destructive.  There are natural consequences for sin, even if God no longer punishes us for them.   But if we obey God then we will become addicted to righteous living.