Deuteronomy 5:13

Moreover also I gave them my sabbaths, to be a sign between me and them, that they might know that I am the LORD that sanctify them.

And they returned, and prepared spices and ointments; and rested the sabbath day according to the commandment.

Six days thou shalt do thy work, and on the seventh day thou shalt rest: that thine ox and thine ass may rest, and the son of thy handmaid, and the stranger, may be refreshed.