When Paul wrote about the law in the New Testament he primarily meant the Mosaic law. However, he also included extensions to that law that were practiced in his day. According to scripture, one purpose of the Mosaic Law is that it served as a tutor leading to Christ (Galatians 3:23-25). It taught those following it none of them could keep their law. Their sacrificial provisions for forgiveness of sins really brought that out to each Israelite. As long as they participated in that religion, they were accepting the idea they were sinners and needed God’s forgiveness. They needed their promised savior.
Compare that to atheists today who don’t feel they need God. They don’t look at themselves as committing sins. Instead they feel as long as they don’t engage in criminal activity they’re fine. But to God they’re lawless, because they reject him and his directions. So the Jewish Law (or religion), by design, was meant to prevent this attitude of self-reliance and turning away from God that is so prevalent today. The Jewish nation was looking for their savior. Their law facilitated this desire of theirs. It turned them to God because their law was their religion, given them by God.
The purpose of that law to lead them to Christ was fulfilled when he came. In that sense Christ fulfilled their law. That purpose was realized; therefore, Christians are not to be led by it as Jews were before Christ came.
Now the law as it is referred to in New Testament scriptures was not often pointing to the type of provisions that are in every governments’ laws for the sake of civility and morality. It is this other aspect of the Jewish law Christians are freed from. But Christians are not free from obeying those parts of the Jewish law that are incorporated into every civil society. Those still serve God’s purpose.
Scriptures teach all Christians still sin. Scriptures also teach all Christians are expected by God not to be lawless (Romans 13:1). Anyone who claims that they no longer sin because they have Holy Spirit is a liar according to scripture (Romans 3:23-see also 1 John 1:8). Any Christian who carries on lawlessness is not part of Christ’s church and will suffer consequences for doing that according to scripture (Matthew 7:21-23). Yet there is no conflict between these ideas, and the concept of salvation due to God’s grace upon believers in Christ, his followers. True all Christians sin, and therefore all are lawless before God. But with God’s help Christians can limit their sin if they choose. Therefore, while members of Christ’s church sin, they do not live the types of lives Christ said will exclude them from his kingdom.
Paul’s instruction not to let ourselves go back under law also included a conceptual idea: not to be ruled by religious ideas added onto scriptural requirements; not going beyond what is written in scripture by following church rules others have added into religious practice-see 1 Corinthians 4:6. Therefore, when Paul wrote Christians are not under law, he wasn’t just referring to the Jewish faith. His idea carries a much broader application. It includes rejecting any stretching of the scriptures that Christian teachers or churches do to coral their flocks into their own pens, with rules that are extensions to scripture. According to Paul, Christians should not submit to Christian teachers or denominations that impose church rules on them as biblical guidelines, when those rules are not biblical.
There are billions of people who are or have been in Christian religious groups that force members to observe non-biblical church rules and laws, under a threat of excommunication for failing to obey those rules. Sometimes excommunication from these groups includes being forever and completely shunned by friends and family members, those who remain inside their religion. In some religions friends and family are forbidden to even say hello upon threat of their own excommunication if they do. Such is the case for members who were Jehovah’s Witnesses, even if they decided to withdraw their own membership without coercion, for any reason.
Christ received similar treatment before his death, excommunicated as an apostate by leaders in his church. Rules imposed on today’s Christian flocks are always taught to be theocratic guidelines. Really? Are they? If similar rules and sanctions were Satanic when imposed on Christ, why isn’t the same status attached to extensions to scripture forced on Christians today, and especially when members are severely punished for not obeying?
Not to go back under law to Paul had a third meaning. It also meant not to believe obeying rules, even scriptural rules, is what saves us or causes us to be forgiven by God. But rather to keep believing we are shown grace by God because we follow Christ, and that is sufficient to save us (John 3:16). Also, see the letters of Romans and Galatians to read more on this important point.