4. Remember the sabbath day to keep it holy. Six days shalt thou labour, and do all thy work. But the seventh day is the sabbath in honour of the Lord thy God; on it thou shalt not do any work, neither thou, nor thy son, nor thy daughter, thy manservant nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates; For in six days the Lord made the heavens and the earth, the sea, and all that is in them, and rested on the seventh day; therefore the Lord blessed the sabbath day, and hallowed it.
That doesn't seem to allow for honoring it every two weeks. And, as I said, this Commandment is at least co-equal with the others. If this were the law (as it has been recently in many places - including my childhood home in Alabama), keeping the Hindu sabbath only would be against the law.
As I said, I appreciate and understand your view of the Commandments. Many who want Christianity to be the basis for our civil law do not.
I know there are Christians who would think my understanding of the universality of the 10 Commandments as wrong. But I doubt that many of them want to start putting people in the stocks for using a car or working on Sunday (for instance, Orthodox Jews don't drive or work on Saturday, but don't expect everyone to follow suit).
I think the main importance right now of the 10 Commandments is that people be allowed to express and practice their religion - including the public display of their tenets - and the public discussion of what this country's laws and founding documents are actually based on. (I don't mean that they are based solely on the Commandments but they are to a large degree.)
I don't see that there is any danger of Christianity (as interpreted by this sect or that) becoming mandatory.