What is the meaning of "va'Hachazakti"?
Rashi: It is an expression of holding. He holds in his hand for support, lest he fall. The continuation proves so - "u'Zero'os Pharaoh Tipolenah", he cannot hold with them.
Why does it say "Tipolenah"?
Rashi: He cannot hold [anything] with his hands.
Radak: It is as if they fell - they have no strength.
Malbim: This is unlike the first time, when the arm was broken, and it can be tied. In the second war, it totally fell; it cannot be fixed.
Why will they recognize "Ki Ani Hashem"?
Malbim: I will put My sword in his hand, and he will stretch it over Egypt.
How will Melech Bavel stretch Hashem's sword over Egypt?
Radak: This is like "Nete Es Matecha" (Shemos 8:12).
Why does it say "El Eretz Egypt"?
Radak: It is like Al; there are many verses like this.
