First of all, Paul didn’t have the authority to overturn one of the Lord’s commandments. Jesus taught us that the Sabbath was made for us, and not the other way around, but we still need a day’s rest each week.I had heard somebody describe really well a few years ago how to explain which OT laws we follow and which ones aren't neccessay. Unfortunately, I forgot.
So how would you explain it?
Some are obvious, like 'Thou shall not steal.' Yet, we do not keep the feasts, circumsize our children on the eigth day, and according to the apostle Paul, the Sabbath need not be observed.
So how would you explain to somebody who maybe confused about all of this? I know, 'love does no harm to a neighbor, therefore love is the fulfillment of the law.' So is that all there is?
Sometimes we need to employ common sense. I believe the Lord was speaking to Jews, and not Christians, when he delivered many of the rules and regulations found in the Old Testament – festivals and upkeep of the temple, for example – but clearly, if homosexuality was a sin for Jews, then it is a sin for all of us. And if Christians want to, they are free to observe ALL of the rules and regulations found in the Old Testament.