Exodus 31:14-15

14You shall keep the Sabbath, because it is holy for you. Everyone who profanes it shall be put to death. a  Whoever does any work on it, that soul shall be cut off from among his people. 15 b  Six days shall work be done, but c  the seventh day is a Sabbath of solemn rest, holy to the  Lord. d  Whoever does any work on the Sabbath day shall be put to death.
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