Jesus fulfilled the Sabbath and inaugurated a new covenant with the celebration on the Lords day, Domenica
Then why aren't you doing the same? Are you better than He?
Paul and the two Marys did stuff on the first day of the week. Okay, what's your point?
The Sabbath was made for man and not the other way around. Seems common sense. God didn't make a special holiday and say I must make somebody to keep it. It was made for our benefit.
Jesus said "If ye love Me, keep My Commandments". Which do you love more? Your denomination or Jesus? Your observance of the Sabbath answers the question.