Exodus 16:23

16:23 He said to them, “This is what the Lord has said: ‘Tomorrow is a time of cessation from work, a holy Sabbath to the Lord. Whatever you want to bake, bake today; whatever you want to boil, boil today; whatever is left put aside for yourselves to be kept until morning.’”

Exodus 16:29

16:29 See, because the Lord has given you the Sabbath, that is why he is giving you food for two days on the sixth day. Each of you stay where you are; let no one go out of his place on the seventh day.”

Nehemiah 9:14

9:14 You made known to them your holy Sabbath; you issued commandments, statutes, and law to them through Moses your servant.