Why does it say "Ki Atah Avinu"?
Refer to 63:16:2:1.
Rashi: It is upon You to look and see our affliction.
Radak: A father does not hold back; he has mercy on his son immediately.
Why does it say "Ki Atah Avinu Ki Avraham Lo Yodanu v'Yisrael Lo Yakirenu Atah Hashem Avinu Go'alenu me'Olam Shemecha"?
Shabbos 89b: In the future Hashem will tell Avraham 'your children sinned.' He will say, 'they should be wiped out for Kidush Hashem.' 1 Hashem asked Yakov; he gave the same response. He asked Yitzchak. Yitzchak said, they are also Your children - You called them "Beni Vechori" (Shemos 4:21)! Also, how much did they sin? Most people live only 70 years. You do not punish for the first 20 2 . Half of the remaining 50 are nighttime, and half the daytime is occupied with prayer, eating, and the Beis ha'Kisei. 3 Only 12 and a half years remain. If You will not bear their sin alone, each of us can bear half. If not, I will bear all of it. I offered my soul for You [at the Akedah]! Yisrael will then say "Atah Avinu." Yitzchak will tell them to direct their praise to Him - "Atah Hashem Avinu Go'alenu me'Olam Shemecha."
Rashi: Avraham did not know us in the affliction in Egypt, and Yakov did not know us in the Midbar, for they already departed. Hashem, You became our father in all of them.
Radak: This is like "Avi v'Imi Azavuni va'Shem Ya'asfeni" (Tehilim 27:10). Even though Avraham is our father, he died many generations ago. A mortal father knows his sons and grandsons only in his lifetime. 4 However, You, our father, live forever. We need only to scream to You. In all generations, past and future, You redeem us from all afflictions, and Your name is always on us. It mentions Avraham, for he is the head of the Avos. It mentions Yisrael, for all his seed is Zera Emes, unlike Yitzchak, who fathered Esav.
Malbim: This explains the complaint about holding back the welling up of Your innards with mercy on us. We have no other father. Avraham does not know us at all, for also Yishmael and Esav come from him; he does not recognize that just we are Am Hashem. Yisrael knew that his sons will be Shivtei Kah, but he did not recognize us with his eyes.
Maharsha (89b): Avraham meant that their sins should be wiped out (pardoned) for the sake of Kidush Hashem. However, one could think that he meant that Yisrael should be wiped out, so Hashem sought a 'better' reply.
Refer to Bereishis 23:1:1:1*.
Kovetz Shitos Kamai DH Amar Lei): People can sin at night (Zenus) and while eating (e.g. Neveilah)! We discuss Beinonim (the primary sin was idolatry - PF). A better answer is that the primary judgment is for Bitul Torah; night was made for sleep (Eruvin 65a). (Did most people spend six daytime hours in prayer, eating and the bathroom?! People used to eat one of the two daily meals at night, and one of the three Tefilos is at night! Perhaps 'eating' includes time engaged in earning income and preparing food. - PF).
Sanhedrin 96a: Avraham became weak when [chasing the four kings] he reached Dan, for he saw that his descendants would serve idolatry there. Yakov's Brachos to Efrayim, Menasheh and his sons show that he foresaw many of their descendants. However, Kinos 26 and 27 (according to Ashkenazi tradition) imply that the Avos did not know about the Churban until Yirmeyah told them! (PF)
What is the significance of "Atah Hashem Avinu Go'alenu me'Olam Shemecha"?
Refer to 63:16:2:1.
Malbim: This explains the complaint "where are Your Kin'ah and Gevurah" (15)? You were always known via this name. Your name is profaned - the Goyim say that You lack ability [to save us]. What will You do about this? Where is Your Kin'ah for Your name?!
