Why does it "v'Atah Hashem l'Olam"?
Rashi: You swore to us in Your name 1 . Just like You always exist, so You should guard Your Shevu'ah forever.
Radak: Everyone in Galus laments that his days are short. Perhaps if his days will extend, he will see the Ge'ulah. Even though I will die, You are forever; You will show the Ge'ulah to those who will be in that generation, and have mercy on Tziyon.
Radak: "Ken Nishbati mi'Ketzof Alayich umi'Ge'ar Bach" (Yeshayah 54:9).
What do we learn from "v'Zichrecha l'Dor va'Dor"?
Radak: Every generation will recognize Your name and pray to You to show the Ge'ulah to them. In some texts, including Ibn Ezra, it mistakenly says v'Chis'acha in place of "v'Zichrecha".
Malbim: Just like You do not change, also Zichrecha, i.e. Your actions, via which people remember You. Even though Your actions are in time, they are unlike other timely matters that cease; they persist for all generations.
