Four Parshiyot

The obligation of hearing the special Maftir on Shabbos Zachor. Different customs, making a Birchas HaMitzvah, women and Zachor, Purim.

The parallel and connection between the four Parshiot, the four cups of the Seder, and the four expressions of redemption.

Judaism strives to mend the Middle East, the Far East, the West, North, and South, this world and all worlds, this generation and prior generations. This is the aspiration of the Jewish people, and no less. This idea is alluded to by the Red Heifer.