Exodus 31:13-16

13“You are to speak to the people of Israel and say, ‘Above all you shall keep my Sabbaths, for this is a sign between me and you throughout your generations, that you may know that I, the Lord, sanctify you. 14You shall keep the Sabbath, because it is holy for you. Everyone who profanes it shall be put to death. aWhoever does any work on it, that soul shall be cut off from among his people. 15 bSix days shall work be done, but cthe seventh day is a Sabbath of solemn rest, holy to the Lord. dWhoever does any work on the Sabbath day shall be put to death. 16Therefore the people of Israel shall keep the Sabbath, observing the Sabbath throughout their generations, as a covenant forever.
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