Isaiah 28:21
ESV
For the Lord will rise up as on Mount Perazim; as in the Valley of Gibeon he will be roused; to do his deed — strange is his deed! and to work his work — alien is his work!
NIV
The Lord will rise up as he did at Mount Perazim, he will rouse himself as in the Valley of Gibeon— to do his work, his strange work, and perform his task, his alien task.
NASB
For the Lord will rise up as at Mount Perazim, He will be stirred up as in the Valley of Gibeon, To do His task, His unusual task, And to work His work, His extraordinary work.
CSB
For the Lord will rise up as he did at Mount Perazim. He will rise in wrath, as at the Valley of Gibeon, to do his work, his unexpected work, and to perform his task, his unfamiliar task.
NLT
The Lord will come as he did against the Philistines at Mount Perazim and against the Amorites at Gibeon. He will come to do a strange thing; he will come to do an unusual deed:
KJV
For the Lord shall rise up as in mount Perazim, he shall be wroth as in the valley of Gibeon, that he may do his work, his strange work; and bring to pass his act, his strange act.
NKJV
For the Lord will rise up as at Mount Perazim, He will be angry as in the Valley of Gibeon— That He may do His work, His awesome work, And bring to pass His act, His unusual act.
What does Isaiah 28:21 mean?
Isaiah has confronted the leaders of Jerusalem for their foolish choice to make an alliance with Egypt (Isaiah 30:1–2) to save them from the Assyrians. He has described the arrangement as a covenant of death and taking refuge in a lie (Isaiah 28:15, 17–18). Not only will the Assyrians bring a hailstorm of destruction on Judah, but their attacks will also be the work of the Lord against His own people.Isaiah says that the Lord will act as He did at Mount Perazim and in the Valley of Gibeon. Israelites would have known these stories. The Lord went before David to strike down the Philistines at Mount Perazim and destroyed the fleeing Amorites with large hailstones in the Valley of Gibeon (2 Samuel 5:17–25; Joshua 10:6–11). Judah should have known from their own history that the Lord could give them victory over their enemies. Instead, they looked for help from other nations.
Now, Isaiah says, the Lord is about to do a strange deed and perform an alien work. Instead of aiming His power against Israel's enemies, the Lord will work against His own people. He will send the Assyrian hailstorm against them for their faithlessness.
