Exodus 20:10

20:10 but the seventh day is a Sabbath to the Lord your God; on it you shall not do any work, you, or your son, or your daughter, or your male servant, or your female servant, or your cattle, or the resident foreigner who is in your gates.

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.