Exodus 6:6
6:6 Therefore, tell the Israelites, ‘I am the Lord. I will bring you out from your enslavement to the Egyptians, I will rescue you from the hard labor they impose, and I will redeem you with an outstretched arm and with great judgments.
Exodus 20:11
20:11 For in six days the Lord made the heavens and the earth and the sea and all that is in them, and he rested on the seventh day; therefore the Lord blessed the Sabbath day and set it apart as holy.