What does Isaiah 5:30 mean?
The Lord has summoned a great army to come and pour out His judgment on His people Israel (Isaiah 5:26). This army will come at His whistle as a trained animal comes running at the summon of its master. The army, likely the Assyrians in this case (2 Kings 24:10–16), will be strong and well-equipped. Every soldier will be alert and well-disciplined. Their equipment will be working and ready (Isaiah 5:27–28). In their toward Jerusalem, they will sound like a lion stalking its prey to carry it off, never to be seen again (Isaiah 5:29).Now Isaiah adds to the soundscape. From a distance the army will darken the land appearing like a storm billowing over the sea. This darkness brings the inevitability of the Lord's judgement upon His people. The time will have come for God's justice to be enacted.