Exodus 31:14-15

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.
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