יחזקאל, פרק מ״ה, פסוק כ״ה

As the time for the dedication of the Third Temple approaches, a special sequence of offerings is outlined for the festivals of the year. During the seventh month, Tishrei, the seven-day festival of Sukkot will feature sacrifices completely identical to those brought during Passover, including the same sin offerings, burnt offerings, grain offerings, and oil. This arrangement presents a striking departure from the original instructions found in the Torah. Traditionally, the festival of Sukkot requires a unique, steadily decreasing number of sacrifices each day, yet the future vision mandates a uniform number of offerings throughout the week. Furthermore, the holiday of Shemini Atzeret, which immediately follows Sukkot, is completely omitted from this new sequence [רד״ק].

To resolve these difficulties, one perspective suggests that the future Messianic era will bring about profound spiritual shifts. According to the Torah, seventy bulls are offered during Sukkot to correspond to the seventy nations of the world. In the future, however, the power of these nations will fade, rendering these specific sacrifices unnecessary. Consequently, Shemini Atzeret, originally intended as an intimate celebration between God and the Israelites after completing the offerings for the nations, loses this specific function and is therefore left out [באר יצחק]. Additionally, highlighting Passover and Sukkot while excluding Shavuot serves to reject the notion that the miracles of the Exodus from Egypt will be forgotten in the future. The festivals that commemorate the Exodus and the protective Clouds of Glory will continue to be celebrated with the same intensity, whereas Shavuot does not require this specific reinforcement [מהר״י].

Despite these symbolic interpretations, the primary approach among commentators is that the traditional Torah laws remain entirely unchanged. The sacrifices detailed for the future are not meant to replace the regular holiday offerings. Instead, they are new, temporary dedication offerings meant specifically for the inauguration of the new altar and Temple, and they will be brought in addition to the standard sacrifices. The future dedication period will be an extended process, beginning in the month of Nisan and concluding on the twenty-first of Tishrei, the final day of Sukkot. Because this inauguration spans from Passover to Sukkot, identical dedication offerings are prescribed for both festivals. This extended period of dedication will also coincide with the time when God judges the nations during the war of Gog and Magog, ultimately bringing about the final salvation [מלבי״ם, אברבנאל].

Under this understanding, the absence of Shemini Atzeret is easily explained. The special dedication period simply ends on the last day of Sukkot. Once Shemini Atzeret arrives, the temporary inauguration offerings will cease, and only the standard sacrifices commanded in the Torah will be brought [מצודת דוד, אברבנאל].