Since you can't find in the New Testament the law of the Sabbath must be kept, then the burden is on you. Since you refuse to prove it, you are wasting our time and get an infraction for Board Etiquette #6.

Paul was referring to that which has long since been established under covenant with Israel which has now passed because the Holy Spirit like Jesus come to fill up the Sabbath's rest. However painful this is for you to accept Rom. 14.5 and Col. 2.16,17, you must accept God's Word.

You are not born-again because you can't have two laws: a law of the Sabbath and the law of the indwelling Holy Spirit simultaneously, for the latter fills up the former. Since you keep the former, you deny the latter and never been quickened in your spirit by the Holy Ghost. How sad.