There are striking similarities between Purim and Passover and one crucial difference that is instructive.
Both holidays are set in the Diaspora—Passover in Egypt and Purim in Persia. Both narratives feature our ancestors speaking truth to power. Moses and Aaron come before Pharaoh and demand that he let our People go (שַׁלַּח אֶת־עַמִּי). Esther asks Ahasuerus to spare her life and the lives of her people (תִּנָּתֶן־לִי נַפְשִׁי בִּשְׁאֵלָתִי וְעַמִּי בְּבַקָּשָׁתִי׃). Both stories celebrate our deliverance from the hands of those who would oppress us (Pharaoh and Haman). There are special foods associated with the holidays as well (matzah and hamantashen).
There is a crucial difference between the holidays which I find instructive. The Purim story ends happily—our ancestors are spared and Haman and his ilk receive their just rewards. Mordechai and Esther are remembered for the good. But the megillah does not go on to tell us the purpose of our deliverance, the price (or reward) of our freedom.
Passover is a celebration of our deliverance from the hand of Pharaoh to be sure but our story goes on to emphasize the “why” of our redemption which is revealed to us at Mount Sinai. The meaning of our salvation is a life of Torah whose central teaching is “love your neighbor as yourself (וְאָהַבְתָּ לְרֵעֲךָ כָּמוֹךָ).”
Passover elevates the celebration of our deliverance by reminding us that true redemption is found in a life of purpose.
— Rabbi Yoshi Zweiback