The significance of the Beis HaMikdash as a kinyan lies in the fact that it is the one place, the one location, where Hashem chose to let His Divine Presence reside on a permanent basis.
Just as the Beis HaMikdash is the place where Hashem has specifically chosen to reside, Yisrael is the nation Hashem has specifically chosen as His. It is the nation upon which the Divine presence rests and the nation through which Hashem’s kavod, His glory, is manifest. We can therefore understand why Yisrael, the Torah, and Heaven and Earth are all called Hashem’s “acquisitions” – because Hashem’s greatness and glory are revealed through them.
That is why He gave the Torah and mitzvos only to Klal Yisrael. By performing the dictates of the Torah and engaging in mitzvos, Klal Yisrael serves as the primary vehicle to bring kavod Hashem into the world.
To encapsulate: Avraham Avinu introduced monotheism and the knowledge of Hashem to the nations of the world, but through his descendants starting with Yitzchak Avinu and continuing with Yaakov Avinu and the twelve tribes, these lessons became purified and distilled until the separate nation of Yisrael became the primary conduit to bring and reveal Hashem’s presence into the world.
Now we can suggest an answer to our original question. Why, during the Yamim Noraim and Sukkos do we so deeply desire that all of the nations recognize Hashem’s kingship over the entire world, whereas on the Yom Tov of Pesach the opposite message – in which we ask Hashem to spill out His wrath on the Nations – comes through?
The Yamim Noraim season marks the anniversary of the creation of the world. At that time, when “the entire world trembles,” it is our wish that the world be restored and reestablished in the way it was originally meant to be, before the creation became distorted by the sins committed by man. During that initial period, the intention was for the entire world to be filled with belief in Hashem and that His honor and glory be manifest and understood by every person in the world. The original Divine plan was that all of creation should feel and experience the presence of the Shechinah, albeit on different levels.
For that reason, we beg Hashem on Rosh Hashanah that the world should be filled with His glory and that every creation should recognize that He is King. That is also why on Sukkos we sacrifice 70 bulls corresponding to the 70 nations. During that period it is our most fervent desire that the world return to its original perfect state, where all the nations will recognize and serve Hashem. In this way we are fulfilling our mandate as “Yisrael kinyan echad” and as descendants of Avraham Avinu.
Pesach, however, marks the birth of Klal Yisrael as a nation after our terrible slavery and subjugation to the Egyptians. The world is not in its original, unspoiled state as intended at the time of creation. Because of our sins we have become subjugated to the nations of the world, a sheep among seventy wolves.
At the time of our recognition of the sad state of affairs caused by our sins, we beg Hashem to pour out His wrath on the nations that are subjugating us and thereby preventing us from properly serving Hashem and spreading His teachings.
On Pesach we say to Hashem, “Look at the difference between us and the nations of the world!” We beg Hashem, from the depth of our very beings, “Master of the Universe! Please have mercy on us and enable us to survive, thrive, and achieve the purpose for which we were placed in this world. We know how imperfect we are, we are aware of our failings and our shortcomings but at least we have a deep desire to serve You. True, we have sinned, but it is our fervent desire to serve You with all our hearts. If you must pour out your wrath, if there must be punishment, let it be upon the nations that have no interest in serving you at all.”