But I will remove far off from you the northern army, and will drive him into a land barren and desolate, with his face toward the east sea, and his hinder part toward the utmost sea, and his stink shall come up, and his ill savour shall come up, because he hath done great things. I will remove far off from you the northern army - "That is, the locusts; which might enter Judea by the north, as Circassia and Mingrelia abound with them. Or the locusts may be thus called, because they spread terror like the Assyrian armies, which entered Judea by the north. See Zechariah 2:13." - Newcome. Syria, which was northward of Judea, was infested with them; and it must have been a northern wind that brought them into Judea, in the time of Joel; as God promises to change this wind, and carry them into a barren and desolate land, Arabia Deserta. "And his face toward the east sea," i.e., the Dead Sea, which lay eastward of Jerusalem. "His hinder part toward the utmost sea," the western sea, i.e., the Mediterranean.
And his stink shalt come up - After having been drowned by millions in the Mediterranean, the reflux of the tide has often brought them back, and thrown there in heaps upon the shore, where they putrefied in such a manner as to infect the air and produce pestilence, by which both men and cattle have died in great multitudes. See Bochart, Hieroz., vol. ii., p. 481.
Livy, and St. Augustine after him, relate that there was such an immense crowd of locusts in Africa that, having eaten up every green thing, a wind arose that carried them into the sea, where they perished; but being cast upon the shore, they putrefied, and bred such a pestilence, that eighty thousand men died of it in the kingdom of Massinissa, and thirty thousand in the garrison of Utica, in which only ten remained alive. See Calmet and Livy, lib. xc., and August. De Civitate Dei, lib. iv., c. 31. We have many testimonies of a similar kind.
Because he hath done great things - Or, כי ki, although he have done great things, or, after he has done them, i.e., in almost destroying the whole country.