Hello, on Reggie’s question, “If God didn’t create the earth in seven days why keep the Sabbath day holy?”
Currently, as a Christian, I don’t. My view from Jer. 31:31, Ez 36, and Hebrews 8, is that we are in the “New Covenant” and so there is no obligation to keep Saturday (Friday sunset to Saturday sunset) in a legalistic sense. I do honor what we call the Lord’s day which is Sunday (His resurrection; the coming of the Holy Spirit)…on Sunday. But the New Covenant is not legalistic works. When Jesus invoked the New Covenant (Luke 22:20), for Christians we are in a much different arena and so the Jerusalem Council directed the new Gentile believers in a few matters of morality but did not direct them to keep the Sabbath or follow circumcision.
First, read the commentary on the web page. Click to the bottom and read the commentary for the phrases “Elohim blessed the seventh day” and “Then made [the seventh day] holy”. The two are related and, I think, speak to your question.
Notwithstanding the commentary above, it’s probably not helpful to read Genesis 2:1-4a (the account of the seventh day) as presaging the Sabbath established in Exodus. While the latter surely and deservedly commemorates the seventh day of creation, the seventh day of creation is not a sabbath day (In fact, it’s not a day at all because it never ends). In the narrative, the significance of the seventh day of creation is not that God rests or ceases, but that His creative work is complete. Done. Fini.
Here’s two articles explaining how the significance of completion is expressed by the author.