Exodus 12:16

12:16 On the first day there will be a holy convocation, and on the seventh day there will be a holy convocation for you. You must do no work of any kind on them, only what every person will eat – that alone may be prepared for you.

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.”

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.