Six days may work be done; but on the seventh is the sabbath of rest, holy to the LORD: whosoever does any work on the sabbath day, he shall surely be put to death.
All Commentaries on Exodus 31:15 Go To Exodus 31
Ambrose of Milan
AD 397
They were also commanded to celebrate the sabbath as a feast on one day of the week, so that they would not be subjected to any burdens. Would that they, who were freed from worldly labors, have departed in such a way. That they would not carry with themselves any burdens of serious sin into that perpetual sabbath of ages to come. But since God knew that the people were fickle, he prescribed for the more feeble a part [of that sabbath] by the observation of one day; he reserved its fullness for the stronger. The synagogue observes a single day; the church observes a day without end. In the law then is the part; in the gospel there is completion. ()..