Since Sep 1, 2012
Before Moses there was no law, sin is not imputed when there is no law. God even protected the first murderer. Abraham did things, marrying his half sister, which was punishable by death under Moses. And yet the Lord made a covenant with Abraham, that if he would believe (rely on, trust in God) that would be counted as righteousness.
Moses gave the law but only to the Jews. The first man who picked up sticks on the Sabbath was executed for it. And just as soon as the law was given the sacrifices began because no one could keep the law.
The law was given to those who think their good work earns approval from God. The Pharisees told Jesus that they kept the law, he replied that if you look at a woman with lust you were guilty of adultery, showing they too had violated the law.
Lawyers, hoping to entrap Jesus, asked what is the greatest commandment. Jesus said to love God with all your heart .and your neighbor as yourself. The lawyer replied that if you did this you would satisfy all the law. Jesus was describing the new covenant.
Jesus gave us this new covenant, not doing away with the Law but fulfilling/perfecting it. The old covenant has been replaced with the new. The law is still in place but is for unbelievers.
We walk in love and so fulfill all the law. Christians are under Grace (unmerited/undeserved favor) and our law (perfect law of liberty) is to love God with all our heart and love others as ourselves (we do this by walking in the Spirit not in the flesh).
Paul wrote extensively about those Jews who were attempting to bring the church back under the law but he said if you go back to the law you make Christ of none effect.
We have a better covenant with better promises. .