1)
Why does it say "Lamah la'Netzach Tishkachenu"?
1.
Rav Sadya Gaon: Do not make us like one who was forgotten permanently.
2.
Rashi: Refer to 5:19:1:1.
3.
Ibn Ezra: Since You exist forever, why do You forget us forever?!
4.
Palgei Mayim: The days of Mashi'ach are called Netzach. He requests, why do You forget us, and not return us to You until the days of Mashi'ach? Why "Ta'azvenu l'Orech Yamim", and wait for us to begin repenting?
2)
What do we learn from "Ta'azvenu l'Orech Yamim"?
1.
Rav Sadya Gaon: Do not abandon us for a long time.
