The law was written in our hearts with new letters.
Here's Paul:
Rom 13:9 The commandments, "Do not commit adultery," "Do not murder," "Do not steal," "Do not covet," and whatever other commandment there may be, are summed up in this one rule: "Love your neighbor as yourself." 10 Love does no harm to its neighbor. Therefore love (agape) is the fulfillment of the law.
11 And do this, understanding the present time. The hour has come for you to wake up from your slumber, because our salvation is nearer now than when we first believed. 12 The night is nearly over; the day is almost here. So let us put aside the deeds of darkness and put on the armor of light. 13 Let us behave decently, as in the daytime, not in orgies and drunkenness, not in sexual immorality and debauchery, not in dissension and jealousy. 14 Rather, clothe yourselves with the Lord Jesus Christ, and do not think about how to gratify the desires of the sinful nature.
Here Paul is using the law, not as a means of salvation (for we already stand saved "in Christ"), but as a standard for Christians living under grace. Yes, we fail...yes we fall short of God's agape love. And when we do knowingly sin the law cant' touch us because of our position "in Christ". Yet still the law is a standard for Christians living under grace.
Now I've gone off into the fruits of salvation. That was not my purpose. My purpose was to discuss the gospel. The problem is you can't see your need of the gospel if it weren't for the law and the conviction of the Spirit. So we've gone off on a tangent and ended up talking about Christian living.
Is this a problem? Yes! If we concentrate on living the good life before we understand the gospel we'll end up with subtle legalism. Been there, done that.
Let's get back to the gospel.