Positive Mitzvah 162;
Negative Mitzvah 325;
Positive Mitzvah 163;
Negative Mitzvah 326

We are commanded to regard the holiday of Shavuot as a sacred holiday. On this holiday, we must stop all our weekday activity (see Negative Mitzvah 325).

This Negative Mitzvah applies to the festival of Shavuot.

We are commanded not to do work on this holiday.

Outside of Eretz Yisrael, this Negative Mitzvah applies to the second day, as well, which is still Yom-Tov.

We are commanded to rest on the first day of the seventh month, the first of Tishrei, which is the holiday of Rosh HaShanah (see Negative Mitzvah 326).

We are commanded not to do work on Rosh HaShanah.

Our Sages declared that this holiday should be celebrated for two days, even in Eretz Yisrael.