Albert Barnes Commentary Isaiah 19:12

"Where then are thy wise men? and let them tell thee now; and let them know what Jehovah of hosts hath purposed concerning Egypt." — Isaiah 19:12 (ASV)

Where are they? - This whole verse is an appeal by the prophet to the king of Egypt concerning the counselors and soothsayers of his kingdom.

The meaning is, ‘A time of distress and danger is clearly coming upon Egypt. They pretend to be wise; and now there is an occasion for all their wisdom and an opportunity to demonstrate it. Let them show it. Let them declare what is coming upon the nation and take proper measures to confront and remove it; and they will then demonstrate that it would be appropriate for Pharaoh to place confidence in them.’

But if they could not do this, then he should not allow himself to be deceived, and his kingdom ruined, by their counsels.