Exodus 31:15-17

Amplified Bible

¹⁵ For six days work may be done, but the seventh is the Sabbath of complete rest, sacred to the Lord; whoever does work on the Sabbath day must be put to death. ¹⁶ So the Israelites shall observe the Sabbath, to celebrate the Sabbath throughout their generations as a perpetual covenant.’ ¹⁷ It is a sign between Me and the Israelites forever; for in six days the Lord made the heavens and the earth, and on the seventh day He ceased and was refreshed.”