Each of the six holidays mentioned above is the subject of a positive commandment to refrain from melakha (constructive labor) as well as a negative commandment against melakha. Thus, there are twelve mitzvot pertaining to resting on Yom Tov. In contrast, there are only two mitzvot that deal with resting on Shabbat – a positive commandment to refrain from melakha and a negative commandment against melakha (Peninei Halakha: Shabbat 9:1). This is because every Shabbat conveys the same message, whereas each holiday has a unique meaning. Accordingly, we are commanded separately concerning each holiday.
The common denominator of Shabbat and the holidays is that in both cases there is a positive commandment to refrain from melakha as well as a negative commandment against melakha. One who refrains from melakha on Shabbat or Yom Tov fulfills a positive commandment, and one who engages in melakha is both negating a positive commandment and transgressing a negative one. Because shevita (refraining from melakha) is a requirement not just on Shabbat but on the holidays as well, holidays are called “Shabbaton” and occasionally even “Shabbat” (Menaḥot 65b).
However, the severity of the restriction on melakha is not uniform. On Shabbat, all melakha is forbidden (see Peninei Halakha: Shabbat 9:1-2), while on Yom Tov, domestic melakha necessary for food preparation is permitted; the only forbidden melakha is that which is work-related (“melekhet avoda”). The general principle is that the holier the day, the more we must submit to divine providence, and the more we refrain from melakha (see below 3:1 and 10:7).
The punishment for Shabbat desecration is also more severe than the punishment for Yom Tov desecration. On Shabbat, if one intentionally performs melakha, despite the admonition of witnesses, the Torah-mandated punishment is death by stoning. If no witnesses are present, he is liable for karet (excision). If he transgresses unintentionally, he must bring a sin offering (MT, Laws of Shabbat 1:1). In contrast, on Yom Tov, if one intentionally performs melakha in front of witnesses, he receives forty lashes. If he does so unintentionally, he is not required to bring a sin offering.
Another difference is that if one unintentionally transgresses several melakhot on Shabbat during a single lapse of awareness, he must offer a separate sacrifice for each melakha transgressed. In contrast, if one intentionally transgresses several melakhot on Yom Tov after receiving one general warning, he incurs only one set of lashes (Makkot 21b; MT, Laws of Yom Tov 1:3).
Each festival has a unique schedule of sacrificial offerings, which differs from that of Shabbat (Bamidbar 28). There are also mitzvot that are specific to the festival and that do not pertain to Shabbat. On Pesaḥ there is a mitzva to eat matza and a prohibition against eating ḥametz. There are also many other mitzvot on the Seder night. On Rosh Ha-shana there is a mitzva to hear the shofar. On Sukkot there is a mitzva to sit in the sukka and to take up a lulav. On Shavu’ot and Shemini Atzeret, there are no special mitzvot, apart from rejoicing, as the main purpose of these two holidays is to serve as an atzeret, a joyous gathering celebrating the culmination of a process. Specifically, Shavu’ot celebrates the culmination of the process beginning with the Exodus and ending in the giving of the Torah (below 13:6), and Shemini Atzeret celebrates the conclusion of the three pilgrimage festivals as well as the culmination of the process of repentance, atonement, and joy.