Genesis 2:1-3 New International Version (NIV)
2 Thus the heavens and the earth were completed in all their vast array.
2 By the seventh day God had finished the work he had been doing; so on the seventh day he rested from all his work. 3 Then God blessed the seventh day and made it holy, because on it he rested from all the work of creating that he had done.
Exodus 20:8-11 New International Version (NIV)
8 “Remember the Sabbath day by keeping it holy. 9 Six days you shall labor and do all your work, 10 but the seventh day is a sabbath to the Lord your God. On it you shall not do any work, neither you, nor your son or daughter, nor your male or female servant, nor your animals, nor any foreigner residing in your towns. 11 For in six days the Lord made the heavens and the earth, the sea, and all that is in them, but he rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy.
Leviticus 23:1-3 New International Version (NIV)
The Appointed Festivals
23 The Lord said to Moses, 2 “Speak to the Israelites and say to them: ‘These are my appointed festivals, the appointed festivals of the Lord, which you are to proclaim as sacred assemblies.
3 “‘There are six days when you may work, but the seventh day is a day of sabbath rest, a day of sacred assembly. You are not to do any work; wherever you live, it is a sabbath to the Lord.