Exodus 13:21

13:21 Now the Lord was going before them by day in a pillar of cloud to lead them in the way, and by night in a pillar of fire to give them light, so that they could travel day or night.

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.