Exodus 35:2
New International Version (NIV)
2 For six days, work is to be done, but the seventh day shall be your holy day, a day of sabbath rest to the Lord. Whoever does any work on it is to be put to death.
From BibleGateway.com: http://www.biblegateway.com/passage/?search=Exodus 35:2&version=NIV
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