Why did they say that they want to build with us?
Rashi: They wanted to cease the building, that it will not be built further.
Metzudas David: They intended to join with us to know what is in our hearts, to find a pretext to cease the work.
Why did they say "Ki Chachem Nidrosh"?
Malbim: The Kusim served b'Shituf - "Es Hashem Hayu Yere'im v'Es Eloheihem Hayu Ovedim." They thought that also Yisrael served so.
Why is Lo written with an Aleph, and we pronounce it as if it has a Vov?
Ibn Ezra: The pronunciation teaches that we offer to Him 1 ; the Kesiv teaches that we do not offer to any other [power].
Malbim: We consider Him the supreme G-d, above all gods. (Malbim does not explain the Kesiv. The verse says that they served their gods! Ibn Ezra can explain, they lied and said that they do not serve other gods. - PF)
When was Esar Chadon Melech Ashur?
Rashi: After Sancheriv settled the Nochrim in Eretz Yisrael 1 , his sons killed him, and Esar Chadon ruled in place of him (Yeshayah 37:38).
And after his entire camp was wiped out. (PF)
