Isaiah 29:5 - Ellicott's Commentary On The Whole Bible

Moreover the multitude... — Better, But. The words interpret those of Isaiah 30:28. The tribulation should be great, but it should last but for a while. As in Isaiah 25:5, the “strangers” — i.e., the “enemies,” and the “terrible ones” — should be brought low. A sudden catastrophe, pointing, probably, to the destruction of Sennacherib’s army, should bring them low. They, too, should pass under the “threshing instrument” of God’s judgments, and be as chaff before the wind.