Why does it say "va'Tizen Ahalah Tachtai"?
Rashi: Refer to 23:5:3:1.
Radak: After she was Ahalah, and she made calves, she was still under Me; Yaravam made them l'Shem Hashem 1 . Afterwards, Achav made Ba'al and served it. This is Zenus ? they abandoned My Avodah and served other gods.
Malbim: Then Ahalah began to serve idolatry and mix with Goyim of other lands.
Just he wanted that Malchus Efrayim will not ascend to Yerushalayim. (PF)
What is the meaning of "va'Tagav"?
Rashi: She lusted. Radak ? this is like "Ma'asu Vach Ogevim" (Yirmeyah 4:30). My father said that this expression always refers to desire for Zenus. Some Piyutim use this word for Hashem's desire. The authors erred!
Why is Ashur called "Kerovim"?
Rashi: They were neighbors, and [Shomron] sent to them [to ask] for help. Menachem ben Gadi (Melachim II, 15:17) paid taxes to Pul Melech Ashur to help him solidify his kingship. The Navi compares this to a woman who is Mezanah. Had they served Hashem, they would not have needed Malchei Ashur!
Radak #1: She lusted for Ashur, and made them relatives.
Radak #2: It is as if they are her relatives. Achaz sent to Melech Ashur "Avdecha u'Vincha Ani Ale v'Hoshi'eni" (Melachim II, 16:7), and then he took the image of the Mizbe'ach from Damesek and said "Elohei Malchei Aram Mazerim Osam Lahem Azabe'ach v'Yazeruni" (Divrei ha'Yamim II, 28:23). Also Malchei Yisrael did so, even if it is not written.
Malbim: They came to their land, i.e. Menachem ben Gadi gave money to Pul Melech Ashur to help him solidify his kingship.