The Sabbath, or Shabbos, is upon Israel, and Judah. If the grafted-in are included, that something for Moshiach ben Dovid to explain. That said, grace covers what we fail to do or stumble over due to our human failings. Too many people use grace as a crutch and assume this gives them a free pass to sin.
That said, Shabbos is for us, foregoing work, even pleasurable work, so as opens up time to pray, worship and communicate with family. It gives us time to walk in G-d's Creation and see the wonders He created. It a time when we can celebrate His love without worrying what to eat (its made ahead) or what to do, (it right before your eyes). It a time to cultivate Shalom from Above and not creation from below.
For in six days HaShem created the heavens and the earth, and He sanctified it. On this day we separate the clean from the unclean, and the Holy from the unholy. This does not mean we need a Goy, Gentile to turn on our lights, back at the time those texts were written getting light was work, not just flicking a switch. That where grace comes in, by the way. Where technology, changes work, "building a fire", to turning up the thermostat, we can sometimes do some things that our ancestors could not.
Yet its a slippery slope, between flicking that switch and starting up the oven. Exactly when we cross over to unclean is likely something those returning to Hahalacha (Hebrew Laws) will need to work out under grace.
