Matthew Poole and continuators on Joel 1:6

6 For a nation is come up upon my land , strong , and without number , whose teeth are the teeth of a lyon , and he hath the cheek teeth of a great lyon .

An innumerable multitude of locusts and catterpillars, called a Nation here, as Solomon calls the Conies and the Ant, Prov. 30.25, 26. A prognostick of a very numerous and mighty Nation, that ere long will invade Iudah.

Or suddenly will come

upon Canaan which God calls his land, or more particularly the two Tribes, Iudea strictly taken,

Mighty in power, and undaunted in courage, if you refer it to the Assyrian or Babylonians; if to those vermin, they are, though each weak by it self, yet in those multitudes which come, strong enough, and irresistible, and shall do Gods work, that is, waste the Land, and devour all before them.

Not simply numberless, but in such multitudes none of you shall be able to recount them.

A strong Lyon, of the middle Age, that hath Whelps, and hunts the prey for them.

Which is old, and the more fierce and terrible in his looks, no way lessened in his strength, and that preys for his young ones, now what waste such Lyons make, such these Locusts will make, such Assyrians will make.

This verse countenanceth their conjecture, who take the locusts and vermin to be Emblematical in part as well as literal; for it seems not very suitable, to call their teeth, teeth of a Lyon.