Enslaved to God.

     That if you confess with your mouth Jesus as Lord, and believe in your heart that God raised Him from the dead, you will be saved;
     for with the heart a person believes, resulting in righteousness, and with the mouth he confesses, resulting in salvation.
                               Romans 10:9-10 NASB

     The problem with sinful man is that he will not submit to the authority of God. He has chosen to live for his own selfish desires, no matter how offensive to God or man they may be. This is what is meant by the mind set on the flesh being hostile toward God. Such an individual wants to be in control of his desires and actions, and will not submit to the law of God, in fact cannot because he has sold himself into bondage to his own selfish desires (Romans 7:5, 8:7).
     This is the work of God, to break the stubborn will of sinful man, and bring Him into subjection to Himself, through the convicting power of the Holy Spirit (John 16:8; Romans 2:4; 1 Thess 1:5; 2 Thess 2:13; 1 Peter 1:2).
     Notice in 1 Peter 1:2 that God, has chosen true believers to obey Jesus Christ, and to be sprinkled with His blood. This is brought about by the working of the Holy Spirit in our lives.
     No one can truly say Jesus is Lord except by the Holy Spirit (1 Cor 12:3). When a man is led to the cross of Christ by the Spirit of God, he will be led to renounce himself, and submit to the reign of Christ in his life. An individual who desires salvation from the penalty of sin without being delivered from the bondage of sin itself, has had a defective experience. For one to desire mercy while still remaining in selfish control of their lives is an anomaly. It cannot be that way, because a stubborn unrepentant heart is still a stubborn unrepentant heart. It is hostile to God, and will not submit to his law, and cannot. One in this situation is still an enemy of Christ(Philippians 3:18-19). They set their minds on earthly things, living for themselves, while calling themselves Christians. Notice that Paul says their end is destruction.
     Jesus points out that it is useless to call Him Lord while we disobey Him (Matt 7:21-23; Luke 6:46). The whole concept of salvation goes beyond forgiveness only; it encompasses an entire change of allegiance, and way of life. This is why Paul says to work out our salvation. He is not saying we earn it by works, he is saying that we are to live out what God is working in us (Philippians 2:12-13).
     Paul makes the point that we are no longer the ones in charge of our lives, once we have come to a saving knowledge of Christ. He tells us this,

     But now having been freed from sin and enslaved to God, you derive your benefit, resulting in sanctification, and the outcome, eternal life.
     For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.
                               Romans 6:22-23 NASB

     Many people look at verse 23 without looking at verse 22. It tells us that we receive the benefits of salvation as slaves of God. In salvation, we are free from sin, no longer to remain in it. We are to be enslaved to God through Jesus Christ as Lord, living a holy and pure life, as He works in in us. We are no longer in control of our lives. He is!
     This is what salvation consist of. The grace and mercy of God through Christ forgives, cancels the debt, and delivers us from sin, but we must yield to Him, giving Him the lordship of our lives. We are no longer our own, as He has purchased us with His shed blood (1 Cor 6:19-20)