In the Judeo-Christian belief, the fourth commandment (in the original telling at Exodus 20:8) reads:
Remember the Sabbath day, and keep it holy. (NRSV)
Or in the retelling at Deutronomy 5:12-14:
Observe the Sabbath day by keeping it holy, as the Lord your God has commanded you. You have six days each week for your ordinary work, but the seventh day is a Sabbath day of rest dedicated to the Lord your God. Deutronomy 5:12-14 NLT
And then there is this version from the Toddler’s Bible:
Save one day a week to praise God.
You get the idea. We do not rest on the Sabbath so we can work during the week, (rather) we work during the week so we can rest and refresh our souls on the Sabbath. And by not working on the Seventh Day, we are affirming that God created the world, and, just as He ceased from work on the Seventh Day, so do we.
Celebrating the Sabbath is not only an act of obedience, it is an act of faith. It is trusting that God will empower us to accomplish all that he has called us to do in six days a week. Moreover, it is a witness to an increasingly godless world. We can have no idea the impact of this act of faith and obedience in the Providence of God.
So, whether you are a Jew or a Christ-follower, pick one of the next two days and celebrate the Sabbath.