Leviticus 23:2-4

2“Speak to the Israelites and tell them: These are my appointed times, the times of the Lord that you will proclaim as sacred assemblies.

3“Work may be done for six days, but on the seventh day there is to be a Sabbath of complete rest, a sacred assembly. You are not to do any work; it is a Sabbath to the Lord wherever you live.

4“These are the Lord’s appointed times, the sacred assemblies you are to proclaim at their appointed times.