I’d not heard the phrase before. It obviously is a more extreme form of 24/7. God didn’t intend us to live at that frantic pace. He gave us one day in seven for us to rest and recharge our batteries. In whatever shape it takes it is a chance to slow down.
When we read of creation in Genesis we see that the morning and evening of each day are mentioned, but not on the seventh day. Does that mean that there will eventually be everlasting rest? I’m not sure of the reason, except that God had finished His work. With the Israelites celebrating the Sabbath it set them apart from their neighbouring nations. The Israelites were emotionally and spiritually free.
On our Sabbaths days we need to do three things. We need to plan them, they need to be intentional. Then they need to be used as extra time to spend with God. And finally they need to be shared with other Christians.