Exodus 24:16

24:16 The glory of the Lord resided on Mount Sinai, and the cloud covered it for six days. On the seventh day he called to Moses from within the cloud.

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 31:17

31:17 It is a sign between me and the Israelites forever; for in six days the Lord made the heavens and the earth, and on the seventh day he rested and was refreshed.’”

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.