The first day that is set apart by God is the weekly Sabbath. The Hebrew construction (hǎššᵉḇî‛î šǎbbǎṯ) forms a superlative, indicating that the Sabbath holds a unique place even amongst these religious festivals. By observing the Sabbath in this way, the Israelites were constantly reminded of what God had done for them. Furthermore, the nation would imitate their Creator, who rested on the seventh day. Ross remarks, By calling for the sanctification of the day, the text helps us understand what activities were stopped, because this day was for spiritual service and not occupational pursuits.
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3 “Six days shall work be done, but on the seventh day is a Sabbath of solemn rest, a holy convocation. You shall do no work. It is a Sabbath to the LORD in all your dwelling places.