…you shall not perform any labor. (Leviticus 23:7)
The Talmud in Shabbos (24b) tells us that, when it comes to melacha (acts of creative labor) on Festivals, there is both a positive and a negative commandment. In the previous mitzvah, we had the positive mitzvah to refrain from labor on the first day of Passover. Here, we have the negative mitzvah, the prohibition against performing acts of labor on that day.
As we mentioned in the previous mitzvah, Yom Tov is different from Shabbos in that labors necessary for the preparation of food are permitted (as per Exodus 12:16).
The basis underlying this mitzvah is as we have said, that we are not meant to spend the Festivals occupied in our usual mundane affairs. We should spend these special days thinking about the reasons God gave us such holidays. In the case of Passover, it is to celebrate the miracles He wrought when He redeemed us from Egypt.
This mitzvah applies to both men and women in all times and places. It is discussed in the Talmud in the tractates of Beitza (8a-9a) and Makkos (21b-22a). It is codified in the Shulchan Aruch in Orach Chaim 495. This mitzvah is #323 of the 365 negative mitzvos in the Rambam’s Sefer HaMitzvos and #147 of the 194 negative mitzvos that can be observed today in the Chofetz Chaim’s Sefer HaMitzvos HaKatzar.