What's a Christian's Relationship to the Old Testament Law?

The question of the Christian's relationship to the Old Testament and to the law is one on which Christ followers themselves disagree. For example, there are Messianic Jews today who follow Christ who feel that they are obligated to obey the Old Testament law. Now they don't think of the law as a source of salvation, but they do think it's a matter of obedience that as Christ followers they should follow the law, at least Jewish Christ followers should. There are some Christian groups that still hold to Seventh-Day Sabbath observance, for example. So the question is controverted, and I think what makes it so difficult is that Jesus' own sayings about the law are very enigmatic. On the one hand he says that anyone who relaxes the least of these commandments in the law will be least in the kingdom of God, and that not a jot or a tittle will pass from the law until all is fulfilled. And yet on the other hand, Jesus himself seemed to relax some of the commandments of the law, saying that it's not what goes into a man that makes him unclean (that is to say, what he eats or drinks), but what comes out of the heart. And Mark the Evangelist says that “thus he pronounced all foods clean.” And when you read the apostle Paul and the decision of the Jerusalem Council as to what to do with Gentiles who convert to Christianity (do they also have to convert to Judaism?), the answer was no, that they weren't obligated to obey all the demands of the law. So for myself I think that we are freed from obedience to all of the demands of the Jewish law, but that nevertheless there are certain central moral principles that are of timeless and enduring value that are affirmed in the law. And the way to spot these is to find where they are reaffirmed in the New Testament in the teachings of Jesus, in the teachings of Paul and the apostles, and when we find them affirming the same moral principles, then I think we can be confident that as Christians we are obligated to obey those aspects of the law that express those moral principles.