Genesis 2:3 (ESV)

3 So God blessed the seventh day and made it holy, because on it God rested from all his work that he had done in creation.

God blesses the seventh day. This day is special because the Lord now enjoys his creation in rest. His divine satisfaction descends on this very day. That is why he sanctifies this day. This means that he sets this day apart and gives this day a special place among the days: a day of holy rest. It is a day when you may enjoy God’s work in peace. The Lord rejoices in his own work (see Psalm 104:31).

Here the Lord imposes a divine order upon our lives. Man is made in his image. Precisely for that reason man is also called to rest on the seventh day after working six days. It is clearly an ordination of creation. This commandment applies since creation. This is also made clear when the Lord mentions in Exodus 20 as the reason for the fourth commandment, For in six days the Lord made heaven and earth, the sea, and all that is in them, and rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy (Exodus 20:11).