How do you know for sure after so many thousands of years, that the day that is observed as the Sabbath at this point in time is the same day as the Seventh day of Creation when God rested?
You can't be serious. The Sabbath was established at Creation and the lives of Adam, Methuseleh, Shem and Abraham overlapped hundreds of years. The Hebrews knew when the Sabbath was after they left Egypt and before the Mt. Sinai event. All of the prophets knew when it was. Jesus never corrected the day of the week. God commanded worship is due Him on the Sabbath but left us no way to know what day that really is? That sounds like desperation on your part.
Read Scripture, the Lord literally communed with Moses, and taught him. He wrote it all down. Follow the calendar set down, and you know all the dates. It is really simple.
If you don’t believe you don’t. If you believe, believe it all.