There are two opposite errors that people sometimes make, when they react to God's law: Judaizing and Nullifying.
Judaizing is the belief that everything from the Old Covenant still applies (in some way) and that we must do our best to follow everything in the Old Covenant law. I think this comes mostly from a faulty reading of Matt. 5:17-19, but we can examine that elsewhere. Paul and the early church were constantly dealing with this error (Gal. 2:14).
Today, because the Christian church has failed to teach the law properly, we have an (understandable) reaction by movements like "Hebrew Roots" who tend to fall into this error. I empathise with them, though, because they are very positive toward God's law, and that's a much better starting point than the next error.
Christians who nullify the law will say, essentially: The law doesn't apply to us today (except maybe for the ten commandments and one or two others). Even though Jesus said that he didn't come to abolish the law (Matt. 5:17), these Christians believe that he did, anyway. Even though Jesus criticized the Pharisees for "making void" the law (Matt. 15:4), these Christians think that Jesus himself "made void" the law. If true, this would make Jesus a pretty big hypocrite, because he was criticizing the Pharisees for doing just that, and he quoted from one of the death penalty statutes in his argument against the Pharisees: Matt. 15:4, Ex.21:17.
Paul made the point that "the law is good, if one uses it lawfully" (1 Tim. 1:8). So what is this "lawful use of the law" where you don't fall into one of the above extremes?
Here are the basic principles:
- You were created by God with a moral nature, so (if you aren't a beast/psychopath) you have at least a rudimentary understanding of right and wrong. This is enough to make you guilty when you sin, but not enough to give you the moral wisdom of Jesus (which is our goal as disciples).
- God expects you to increase in your moral maturity and wisdom throughout life. He gave you His law to help guide you toward His own character.
- The better your moral decision-making, the better off you will be in this life. This is not a "prosperity gospel" promise, it is from God Himself: Deut. 12:28.
- The more you understand the law, the more you will realize that it does not limit your freedom, it guarantees it. Biblical law is like a series of firm paths through a swamp. Stay on one of the branches of these paths, and you won't get eaten by alligators or sink into the mire. That is true freedom.
- You will also figure out what your pastor probably never told you, which is that Biblical law radically limits the authority of the church and the civil government over you. I think this is one reason why churches don't teach the law. Men in power don't like it when you show them the limits of their power, but it's better that they find out sooner, rather than later, when they are usurping God's authority.
- Christians have supported antinomianism and Phariseeism in church and civil government, throughout history. It's time that changed, and it starts with you in your local church and community. Know the law, teach it to your children, teach it in your church (and leave your church if they don't like it). Become the person that people know can give a thoughtful, Biblical answer. Don't try to change your pastor or elders. Just give everyone the truth when they ask, and don't participate in Phariseeism or antinomianism.
- There is no need to "fight" (speak harshly, get angry, label people "heretics") over interpretations of the law. Does someone you know think that the food laws should be followed, but you think that they are not longer in effect? That's fine. Don't dispute, if you are both convinced in your own minds. In his household, his interpretation holds. Respect the jurisdictional boundaries. Most of these issues are conscience issues, not central to Christian fellowship. Argue the issue with respect; don't fight. In Christ, there is more that unites you, than divides you.