Originally posted by: newParadigm
For us, living after Christ, his commands define what is right and wrong for those of us who aspire to live faithful to God. Christ worked on the sabbath, if the law defines sin, than it wouldn't have been possible for him to be the perfect sacrafice based on your logic.
Jesus healed on the Sabbath. This was a "law" established by the Saducees and Pharisees at the time, not a Levitical law. I forgot the exact number of added rules that the Pharisees did, because it has been over 4 years since I really read anything on this. If you get a chance, read Norman Geisler (famous modern theologian). The Levitical law requires that you do not work on the day of the Sabbath, meaning plow the field... Was what Jesus did "work"?
If you get a chance, read through Romans 3-8, and let me know what you think.

BTW, I included some passges,
WARNING: so this post is long and somewhat verbose. Don't read it if you don't want to. No proselytizing here.
Romans 3:27-28 - Where, then, is boasting? It is excluded. On what principle? On that of observing the law? No, but on that of faith. For we maintain that a man is justified by faith apart from observing the law.
Romans 5:20 - The law was added so that the trespass might increase. But where sin increased, grace increased all the more...
Romans 6:1-2 - What shall we say, then? Shall we go on sinning so that grace may increase? By no means! We died to sin; how can we live in it any longer?
Romans 6:13-14 - Do not offer the parts of your body to sin, as instruments of wickedness, but rather offer yourselves to God, as those who have been brought from death to life; and offer the parts of your body to him as instruments of righteousness. For sin shall not be your master, because you are not under law, but under grace.
**If we submit our lives to God, he is our Master and sin will not reign in us, but sin is dead. But if we live under the law, the law is what will guide our righteousness (but ultimately we will fail), that is why it is righteousness through faith because otherwise we fail (Romans 2, 3:23)**
Romans 7:7-25
What shall we say, then? Is the law sin? Certainly not! Indeed I would not have known what sin was except through the law. For I would not have known what coveting really was if the law had not said, "Do not covet." But sin, seizing the opportunity afforded by the commandment, produced in me every kind of covetous desire. For apart from law, sin is dead. Once I was alive apart from law; but when the commandment came, sin sprang to life and I died. I found that the very commandment that was intended to bring life actually brought death.
For sin, seizing the opportunity afforded by the commandment, deceived me, and through the commandment put me to death. So then, the law is holy, and the commandment is holy, righteous and good. Did that which is good, then, become death to me? By no means! But in order that sin might be recognized as sin, it produced death in me through what was good, so that through the commandment sin might become utterly sinful.
We know that the law is spiritual; but I am unspiritual, sold as a slave to sin. I do not understand what I do. For what I want to do I do not do, but what I hate I do. And if I do what I do not want to do, I agree that the law is good. As it is, it is no longer I myself who do it, but it is sin living in me. I know that nothing good lives in me, that is, in my sinful nature. For I have the desire to do what is good, but I cannot carry it out. For what I do is not the good I want to do; no, the evil I do not want to do?this I keep on doing. Now if I do what I do not want to do, it is no longer I who do it, but it is sin living in me that does it.
So I find this law at work: When I want to do good, evil is right there with me. For in my inner being I delight in God's law; but I see another law at work in the members of my body, waging war against the law of my mind and making me a prisoner of the law of sin at work within my members. What a wretched man I am! Who will rescue me from this body of death? Thanks be to God?through Jesus Christ our Lord!
So then, I myself in my mind am a slave to God's law, but in the sinful nature a slave to the law of sin.
**The law is not sin. The law is holy, but it is what defines what sin is.**
Romans 8:1-4
Therefore, there is now no condemnation for those who are in Christ Jesus, because through Christ Jesus the law of the Spirit of life set me free from the law of sin and death. For what the law was powerless to do in that it was weakened by the sinful nature, God did by sending his own Son in the likeness of sinful man to be a sin offering. And so he condemned sin in sinful man,in order that the righteous requirements of the law might be fully met in us, who do not live according to the sinful nature but according to the Spirit.
**Because the law and sin doesn't govern us then, how do we live a life without sin? By living according the the Holy Spirit and pursuing a relationship with G-d**