The sabbath and all the Mosaic laws of the OT were shadows pointing to the coming of Jesus (New Testament). The 4th commandment (the sabbath one) was a labor law back in those days. Sin was under the authority of death.

Jesus replaced the law as our authority. The coming of Christ cancelled all 613 laws (not just the Big Ten) when they were all nailed to the cross. We are no longer judged and put to death in regard to a sabbath day, weekly, monthly, or yearly celebration, or for eating such and such, etc.

Jesus fulfilled the laws of sin and death, and now we have rest and eternal life in Him. All the OT signs (keeping the sabbath, circumcision,,,,,) have been replaced with Jesus. The sabbath is about resting in Jesus because of his finished work.