Isaiah 28:21
For the LORD will rise up as on Mount Perazim. He will be angry as in the valley of Gibeon; that he may do his work, his unusual work, and bring to pass his act, his extraordinary act.
World English Bible (Public Domain)
In context
Before · Isaiah 28:19–20
19As often as it passes through, it will seize you; for morning by morning it will pass through, by day and by night; and it will be nothing but terror to understand the message.” 20For the bed is too short to stretch out on, and the blanket is too narrow to wrap oneself in.
21For the LORD will rise up as on Mount Perazim. He will be angry as in the valley of Gibeon; that he may do his work, his unusual work, and bring to pass his act, his extraordinary act.