When we read through the Torah, and when we go over the calendar, we can immediately see a unique fact about Sukkot. It is in the end of two different cycles of holidays. It is the end of the Tishrei cycle, being the last holiday after Rosh Hashana and Yom Kippur, and also the third of the cycle of the Shalosh Regalim, which include Pesach and Shavuot.
The special thing about this fact is that the two cycles seem to be reversed, and even contradictory. The Regalim system is a system based on the story of יציאת מצרים and in that way, is an only-jewish cycle, while the Tishrei cycle is much more universal dealing with crowning Hashem as king of the world, and the judgment of all creatures.
Rav Zvi Yehuda Kook explains, that by connecting Sukkot to both cycles we should understand that the two cycles will eventually have a strong connection. Am Israel is a unique phenomenon in the world, but our goal is to make the entire world better. The development and Torah that Am Israel brings to the world shouldn’t stop only in the small capacity of our own nation. We should constantly try to bring our voice to all nations, until the whole world will be full of Hashem’s will and Torah.
Sukkot is the only holiday that can do that job because of its combination of spirituality and materialism. During sukkot we celebrate both our agriculture achievements, and the end of the judgment of the world. Combining both spiritual and actual work together is a true start up - teaching the world a new way to approach life. Connecting spirit and matter in a new and deep way.
Maybe this is why the נביא teaches us that the whole world will come to worship Hashem especially during Sukkot because Sukkot is the one holiday that speaks both spirit and matter. And as we all pray, we will finally see the day that Hashem and his name will be united, by all means and people.