The Seventh Day Sabbath

The seven day sabbath is taken away in the hebrew old testament. The rest days that were associated with and built upon, right? Right? And particularly the sabbaths that fell on days other than the seventh day of the weekt incorporates those things. We're seeing a theme here, aren't we? These three words or phrases put together have reference to all the days that israel was to observe. They are distinctively jewish. Tell me some reason why paul doesn't use this language in the same way every other time it's brought together in the old testament. I think you have an exgetical reason to say there's something different here.