" What then? Shall we sin because we are not under the law but under grace? By no means! Don’t you know that when you offer yourselves to someone as obedient slaves, you are slaves of the one you obey—whether you are slaves to sin, which leads to death, or to obedience, which leads to righteousness? But thanks be to God that, though you used to be slaves to sin, you have come to obey from your heart the pattern of teaching that has now claimed your allegiance. You have been set free from sin and have become slaves to righteousness."
The Spirit of sin that dwells in us make us to sin. So when we abondone sinning and don't keep the faith of righteousness, the Spirit of sin overcomes us to sin & therefore we become slaves to sin. So for those who are in drunkeness, fornication, criminals, worshipping idols are slaves to these sins, because they aren't able to do away with these sins. Then if that is the case, should we say that the spirit of sin is powerful than the spirit of righteousness? Because many people are been disturbed by these sins than those who are righteous. It's obvious that many people are reluctant to give their sins, because they are been controlled. But, if the will power is there, if the mindset and the faith to follow our Almight leads our lives, then the spirit of sin can't control our lives.
Because, the Bible says that Jesus Christ came unto the Earth so that we will have abundance of grace, but the Devil came to steal (John 10:10) and over shadow our vision and mission why we are here. That is to make us slaves to shut this vision down so that we can follow him to hell. Why we continue to sin no matter the amount of Gospel preached is something mystry. Because Jesus Christ has cleansed our sins, and by this time we shouldn't mingle ourselves with sins. But the Devil have deployed his agents to win souls to his Kingdom, and because that we have been hidden from the truth. Our ears have been closed from what is coming which is even on our door steps and very near.
If we were created in God's own image, resemble him of course, then why do we still sin, because God is perfect in all aspect. God first gave us "choice" to choose from when Adam and Eve were created. That was to select from the Garden of Eden, except with the fruit of knowledge and wisdom. Out of here, we failed by making our own choice of taste this forbidden fruit. Through this, we implanted the spirit of sin within us. What we know is that, the spirit of sin and the spirit of righteousness are in opposite reaction with each other. One must over come us. The Almighty God who have all power having this spirit of righteousness rejected us and sent us unto the Earth to make our lives. So, the Spirit of sin already controlled the Earth. Before this, the Lucifer has already been overthrown from God's Kingdom because of the arrogance He seemed to possessed against God. If that is the case, then it means that the Spirit of sin existed before the creation of Adam and Eve of which in our thoughts brought sin to mankind.
In conclusion, one can be slave to sin if he doen't believe and follow Jesus Christ. Because that person would have enough Spirit of righteousness to conquer the the spirit of sin. However, for those who embed their hopes in our Lord Jesus Christ, fulfill his will and teachings aren't slaves since they might over come sins. If we really want to be unslaved by the spirit of sin and multiply through sins, then we should strive to accept Jesus, believe that God is the ruler of this Earth.