The Sabbath was a prescribed day of rest in ancient Israel. As New Testament people, that specific law doesn't apply to us the same way. But rest brings re-creation, and it's a good thing.
Jesus fulfilled the Old Covenant, keeping the law of God perfectly. He kept the Sabbath, the day of rest on the seventh day of the week. And now, we New Testament Christians, we are freed from needing to observe that day in the same was as ancient Israel. We now find our sabbath rest in Jesus (Colossians 2:16-17, Hebrews 4:8-10); we don't have to work to enter the rest of God.
But because we are assured of our salvation, we do work. The order is critically important. We work hard, but not to try to earn God's favour. We work hard to serve our neighbour because we already have God's favour in Jesus.
And Sabbath rest for us now looks different. I like Eugene Peterson's simple definition: pray and play. For us the Third Commandment now takes the shape of hearing God's Word in worship and taking time to recreate. Though it's certainly not a law, we generally do this now not on the seventh day, but on the eighth day, the Lord's Day, the day of the resurrection which leads us to re-creation too.
And it has a more informal shape. A weekly pattern of rest is simply good for us. And that doesn't mean doing nothing for an entire day (though, if your vocations allow it, it can mean that). But it can also mean having a change of pace, doing different things. Leisure things, yes, but needed things too, just in a different way, at a different pace.
It's not a law, but it is good for us. In today's age, that's what Sabbath looks like. It's intended for our recreation, the re-creation and renewal of body and soul.