Strangers: Required to Observe the Sabbath Day
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Exodus 20:10
but the seventh day is a Sabbath to the LORD your God, on which you must not do any work—neither you, nor your son or daughter, nor your manservant or maidservant or livestock, nor the foreigner within your gates.
Exodus 23:12
For six days you are to do your work, but on the seventh day you must cease, so that your ox and your donkey may rest and the son of your maidservant may be refreshed, as well as the foreign resident.