Judaism offers many opportunities for rejoicing, gladness and delight, chief among them being the three Pilgrim Festivals of Pesach, Shavuos and Sukkos. Concerning these festive days G‑d commands us: “You shall rejoice in your festival....”1

Pesach commemorates the Jews’ physical exodus from Egypt; Shavuos — their receiving the Torah; Sukkos — their protection in the desert from the sun’s searing heat by the Clouds of Glory.2 Of the three festivals, Shavuos is obviously the most spiritual in nature, commemorating as it does an entirely spiritual event.

The three Pilgrim Festivalsare supposed to be celebrated not only with prayer and study but also with fine food and drink.3 In certain circumstances, however, the delight of Pesach and Sukkos may be expressed in a wholly spiritual manner, foregoing food and drink. Such would be the case when one fasts during these holidays on account of a distressing dream.4

This is not so with regard to Shavuos. On Shavuos we are obliged to “eat and rejoice, demonstrating that Jews are pleased and gratified with the day on which the Torah was given.”5 Fasting on Shavuos because of a disturbing dream is prohibited.6

It seems paradoxical that Pesach and Sukkos, the two festivals that commemorate primarily physical events, may be celebrated in a totally spiritual manner, while Shavuos, which commemorates an event that is completely spiritual, must be celebrated not only spiritually, but also physically. Why must Shavuos be so celebrated?

Shavuos is unique in that the revelation of G‑dliness that accompanied the Giving of the Torah penetrated all of creation. In the words of our Sages: “The sound of G‑d’s giving the Torah arrived from all four directions as well as from above and below.”7 So awesome and all-encompassing was this event that “no bird chirped; ... no cow lowed; ... the world was silent and held its peace.”8

Moreover, the sound of the Giving of the Torah infused everything, even the inanimate. Therefore, say our Sages, this sound did not produce an echo.9 An echo results when sound waves are not absorbed by an object, but bounce off it. Since the sound of G‑d’s giving the Torah penetrated all matter, it was impossible for the sound to be echoed.

This was so because when the Torah was given, G‑d’s quintessential Essence was revealed, for G‑d imbued the Torah with His Essence.10 Since G‑d is the only entity that is truly infinite, it follows that at the time the Torah was given — when His Essence was revealed — nothing was impervious to this revelation; it penetrated and infused all of creation, even the grossest of corporeal matter.

A holiday that celebrates the ultimate in spiritual revelation and which also infuses all of creation without limitation must itself be celebrated in a truly revealed manner and without limitation, up to and including celebration that is manifested in a physical way, i.e., through eating and drinking.

If fasting because of a distressing dream were permitted on Shavuos, this would indicate that there remained a level in the universe that was impervious to the joy of Shavuos. This would be contrary to the spirit of the festival as a whole, which proclaims that even the nethermost level is “pleased and gratified” with receiving the Torah.

Thus, Shavuos affects even an individual who is so distressed that at any other time of the year it would be impossible for him to derive pleasure from food. Shavuos and its accompanying joy transform even this troubled individual, for he, too, is “pleased and gratified” with receiving the Torah.

Based on Likkutei Sichos, Vol. IV, pp. 1092-1096; Vol. XXIII, pp. 27-32.