וְכָל־הַנֶּ֗פֶשׁ אֲשֶׁ֤ר תַּעֲשֶׂה֙ כָּל־מְלָאכָ֔ה בְּעֶ֖צֶם הַיּ֣וֹם הַזֶּ֑ה וְהַֽאֲבַדְתִּ֛י אֶת־הַנֶּ֥פֶשׁ הַהִ֖וא מִקֶּ֥רֶב עַמָּֽהּ׃
And whatsoever soul it be that doeth any manner of work in that same day, that soul will I destroy from among his people.
Read kabbalistic (mystical) interpretation of Leviticus 23:30: and classical mystical sources.