What is "Aruchah"?
Rashi: It is a cure.
Is "umi'Makosayich Erpa'ech" the same as "A'aleh Aruchah Lach"?
Malbim: No. Aruchah is a cure for the external breakage. Makosayich are your inner wounds.
Why does it say what others called you?
Malbim: It explains why they will not be punished. Do not say that they should be exempt, for they were Hashem's messengers to harm you. They said that Tziyon is abandoned; Hashem will not return it. They did not consider you like a son who sinned against his father, and his father handed him over to someone to afflict him, so he will return from his evil way. That Shali'ach must be careful not to perish him, only to afflict him as needed to make him repent, and with great mercy.
What is the meaning of "Doresh Ein Lah"?
Rosh Hashanah 30a: This teaches that we need to seek Tziyon. This was the source to take the Lulav all seven days outside the Mikdash, to commemorate the Mikdash.
Radak: The nations say that there is no one who seeks to return it to Yisrael.
Malbim: The nations say that Hashem abandoned Tziyon and will not return it to Yisrael, and no one will claim for it and seek [vengeance for] its blood from their hands, therefore they utterly destroyed it.
