Leviticus 23:1-3

The LORD said to Moses, “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. “ ‘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.