"An important distinction between the two texts on this 
commandment is
their grounding in creation and redemption, respectively.
In Exodus, the
Sabbath is rooted in the six days of creation followed by a day of rest
(Gen. 1:3-2:3).
Deuteronomy adds the element of God’s redemption. “The Lord your God
brought you out from there with a mighty hand and an outstretched arm;
therefore the Lord your God commanded you to keep the sabbath day” (Deut. 5:15).
Bringing the two together, we see that the foundations for keeping the
sabbath are both the way God made us and the way he redeems us." TOW