They are mistaken! The Sabbath & all the Sabbaths belong to YHVH Elohim from the beginning of time. Even if man does not keep them YHVH runs this whole universe on the signs, seasons, days & years that He instituted in Genesis which includes ALL the Sabbaths. Weekly Sabbaths, yearly Sabbaths, weeks of years, Jubilee's. These all run on the 7th day Sabbath system. All Feasts & festivals are calculated by the weeks, months & ALL are based on the weekly Sabbath established at creation for all mankind. Adam & Chava would have done exactly as their Father did & Abba YHVH rested on the 7th day. They were neither jew nor gentile but YHVH's creation. After 400 years in egypt YHVH again reminded the Israelites of the 7th day & re- instituted it before the commandments were given & again it was for all as there was a mixed multitude of servants & strangers who also had to observe the Sabbath. Goodness me even the animals had to rest, so how much further can we go to refute this as animals are neither jew nor gentile, but YHVH's creation.