Mark 2:27 says that the Sabbath (rest) was made for man, not man for the Sabbath, (man, to worship (work) to observe a day).
The soul of man has a natural tendency to seek to be productive, and so attempts continually to build its own standard apart from Christ, attempting to do it so even with a Sabbath day.
Due to iniquity in the soul, God must circumcise and cleanse the soul. So, as we submit to His work of redemption in the New Covenant to enter into His rest (Sabbath), the soul ceases to work with iniquity, this being the entering into His rest.
Christ is Lord of the Sabbath, for from Him, and not from the observance of a day (man’s own religious standard) do we have His rest in our redemption.
Our rest from the works of iniquity is in a living Christ, who became our Sabbath. Welcome to rest as God establishes us