Isaiah 18:5 - Joseph Benson’s Commentary on the Old and New Testaments

For afore the harvest Here the Lord informs his people how he would act toward those of their adversaries, for whom he had prepared this great slaughter. He compares them to a vine, which, after it hath sent forth its buds, then its flowers, and the flowers the sour grapes, which too were beginning to ripen, is suddenly stripped of its shoots and branches by the pruning-hook of the vine-dresser, who leaves them, burdened with grapes, a prey to the fowls of heaven, and the beasts of the earth. By which allegory, continued through this and the sixth verse, the prophet means, that, when every thing respecting the Assyrians was in the most promising situation, when Sennacherib's great designs seemed almost mature, and just ready to be crowned with success, his mighty efforts should be in a moment frustrated, his vast expectations rendered abortive, and the chief part of his immense army made a prey to the beasts and birds.