Jerome : (Verse 5.) And the people will fall, man against man, each one against his neighbor: the young will rise up against the old, and the lowly against the noble. When the young become leaders and mockers of the Lord, as the prophetic word describes, then no order of dignity, age, or knowledge will be preserved; but the young will rebel against the elderly, and the lowly against the noble, and they will fall together. And that Apostolic saying will be fulfilled: biting each other, you have been consumed by each other (Galatians 5:15). Josephus writes in Book 5 of The Jewish War that these events happened to the people of Judaea under Titus, son of Vespasian: that when they were being besieged by the Romans, there was a division of the city into three parts due to the rebellion. Some held the citadel and the Temple, others held the lower part of the city, and others held the upper part. — Commentary on Isaiah