An exposition of Romans 10:4, which says: "Christ is the end of the law so that there may be righteousness for everyone who believes," will help in understanding what is means that Christians are not under the law. The apostle Paul clarifies the effects of original sin in Romans 2:12, stating "All who sin apart from the law will perish apart from the law, and all who sin under the law will be judged by the law." All men stand condemned before God, whether they are Jews or not, or to put it another way, whether they have the Law of God or not. Paul also states "For all have sinned and fall short of the glory of God" (Romans 3:23).
If we are without Christ, we are justly condemned in God’s sight by the Law that was given to His servant Moses. However, we might argue that those who are not Jewish and therefore do not benefit from the knowledge of the Mosaic Law (including the moral and ceremonial laws), should not be condemned in the same way. This is dealt with by the Apostle in Romans 2:14-15, where he states that the Gentiles have the essence of God’s legal requirements already ingrained and so are just as much without excuse.
The Law is the issue that has to be dealt with in order to bring us into a right relationship with God. "Know that a man is not justified by observing the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by observing the law, because by observing the law no one will be justified" (Galatians 2:16). This passage reveals that the Law cannot justify or make righteous any man in God’s sight, which is why God sent His Son to completely fulfil the requirements of the Law for all those who would ever believe in Him.
Christ Jesus redeemed us from the curse that has been brought through the law by becoming a curse for us (Galatians 3:13). He substituted Himself in our place and upon the cross took the punishment that is justly ours so that we are no longer under the curse of the Law. In doing so, He fulfilled and upheld the requirements of the Law. This does not mean that Christians are to be lawless, as some advocate today—a teaching called antinomianism. Rather, it means that we are free from the Mosaic Law and instead under the law of Christ, which is to love God with all of our being and to love our neighbors as we love ourselves.
Christ became the end of the Law by virtue of what He did on earth through His sinless life and His sacrifice on the cross. So, the Law no longer has any bearing over us because its demands have been fully met in the Lord Jesus Christ. Faith in Christ who satisfied the righteous demands of the Law restores us into a pleasing relationship with God and keeps us there. No longer under the penalty of the Law, we now live under the law of grace in the love of God.