As it Appears in the Ten Commandments in the Book of Deuteronomy 5, 12-15

 

Keep the Shabbat day to sanctify it, as G-d your Lord has commanded you. Six days you shall labor, and do all your work:  And the seventh day is the Shabbat of G-d your Lord, you shall not do any work, you, nor your son, nor your daughter, nor your manservant, nor your maidservant, nor your ox, nor your ass, nor any of your cattle, nor your stranger that is within your gates; that your manservant and your maidservant may rest as well as you.

And remember that you were a servant in the land of Egypt, and that G-d the Lord brought you out there with a mighty hand and an outstretched arm: therefore G-d the Lord commanded you to keep the Shabbat day.