Sifrei Mitzvot untuk Imamat 23:21

וּקְרָאתֶ֞ם בְּעֶ֣צֶם ׀ הַיּ֣וֹם הַזֶּ֗ה מִֽקְרָא־קֹ֙דֶשׁ֙ יִהְיֶ֣ה לָכֶ֔ם כָּל־מְלֶ֥אכֶת עֲבֹדָ֖ה לֹ֣א תַעֲשׂ֑וּ חֻקַּ֥ת עוֹלָ֛ם בְּכָל־מוֹשְׁבֹ֥תֵיכֶ֖ם לְדֹרֹֽתֵיכֶֽם׃

Pada hari itu juga kamu harus mengumumkan pertemuan kudus; hari itu harus menjadi pertemuan kudus bagimu. Janganlah kamu melakukan pekerjaan berat apa pun. Ini adalah ketetapan untuk selama-lamanya di semua tempat tinggalmu, turun-temurun.

Mishneh Torah, Rest

These six days on which Scripture prohibited labor—being the first and seventh days of Passover, the first and eighth days of Sukkot, the day of Shavuot and the first day of the seventh month (Rosh Hashanah)—are called holidays (yamim tovim). The [degree of] cessation of work is equal in all of them, in that all work is prohibited except for labor that is for the sake of eating—as it is stated (Exodus 12:16), "only anything that is eaten by any person."
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Sefer Hamitzvot of Rasag

Shavuot
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