Matthew Poole and continuators on 2 Kings 19:9

9 And when he heard say of Tirhakah king of Ethiopia , Behold, he is come out to fight against thee: he sent messengers again unto Hezekiah, saying,

Heb. of Chush, i. e. Either, 1. of Arabia, as that Word is most commonly meant; of which see the notes, and especially my Latin Synopsis, upon Numb. 12. 1. Or rather, 2. Of Ethiopia beyond Egypt. Nor was there any need that he should force his Passage through Egypt, which is objected against this Opinion by a very Learned Man; because the Egyptians (against whom this Sennacherib Warred, as Heathen Historians, Herodotus and Berosus, relate) and the Ethiopians were Confederates in this Expedition, as Iosephus expresly affirms; who lived above 1600 Years nearer the time when this was done, than we; and therefore was more likely to understand it.