Exodus 12:17-18

12:17 So you will keep the Feast of Unleavened Bread, because on this very day I brought your regiments out from the land of Egypt, and so you must keep this day perpetually as a lasting ordinance. 12:18 In the first month, from the fourteenth day of the month, in the evening, you will eat bread made without yeast until the twenty-first day of the month in the evening.

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 31:15

31:15 Six days work may be done, but on the seventh day is a Sabbath of complete rest, holy to the Lord; anyone who does work on the Sabbath day must surely be put to death.

Exodus 35:2

35:2 In six days work may be done, but on the seventh day there must be a holy day for you, a Sabbath of complete rest to the Lord. Anyone who does work on it will be put to death.