What do we learn from "v'Ad Ziknah Ani Hu v'Ad Seivah"?
Rashi: When You became old and your strength ceased, that you have no merit, I will save you with My mercy and Midah of Tov.
Radak: I am with you until Ziknah (60 years old) and Seivah (70).
Radak (3) #1: Refer to 45:3:3:2.
Radak (3) #2: Great bearing and support is needed. Whenever you will be in affliction, I will bear you.
Malbim: Hashem bears His children more than parents bear their children. Parents raise children only until they grow up. Afterwards, it is reversed
Why does it say "Ani Asisi va'Ani Esa"?
Radak: Since I made and raised you, it is upon Me to bear you. It is a metaphor to discuss a burden on Hashem.
Malbim: Idol worshippers must carry the idols, because they made them. I made you, and I bear all your needs, and save you from every mishap.
Why does it say "va'Ani Esbol va'Amalet"?
Rashi: Because it says about the idols "Lo Yachlu Malet Masa" (2)
