1)
Where do we find that they feared the sword?
1.
Rashi: They turned to the king of Egypt for help, like it says about Tzidkiyah "va'Yimrad Bo Lishlo'ach Mal'achav Mitzrayim" (17:15).
2)
What is the significance of bringing a sword against them?
1.
Radak: He will bring the same sword that they feared (Melech Bavel), and Egypt will not save them.
2.
Malbim: The wall will not be like a pot to save you, for I will bring a sword against you.
