God had before compared himself to a lion, Jer_25:30; here he declares himself to be about to move like a lion, who when he goeth out to seek his prey, leaveth his covert: see Jer_50:44. The effects of this rising up of God out of his covert is the desolation of the land through the fierceness of the enemy, caused from the fierce anger of God now ready to be poured out upon this people.