nation - applied to the locusts, rather than “people†(Pro 30:25, Pro 30:26), to mark not only their numbers, but also their savage hostility; and also to prepare the mind of the hearer for the transition to the figurative locusts in the second chapter, namely, the “nation†or Gentile foe coming against Judea (compare Joe 2:2).
my land - that is, Jehovah’s; which never would have been so devastated were I not pleased to inflict punishment (Joe 2:18; Isa 14:25; Jer 16:18; Eze 36:5; Eze 38:16).
strong - as irresistibly sweeping away before its compact body the fruits of man’s industry.
without number - so Jdg 6:5; Jdg 7:12, “like grasshoppers (or “locustsâ€) for multitude†(Jer 46:23; Nah 3:15).
teeth ... lion - that is, the locusts are as destructive as a lion; there is no vegetation that can resist their bite (compare Rev 9:8). Pliny says “they gnaw even the doors of houses.â€