Charles Ellicott Commentary Isaiah 33:11

"Ye shall conceive chaff, ye shall bring forth stubble: your breath is a fire that shall devour you." — Isaiah 33:11 (ASV)

Ye shall conceive chaff ... — Primarily the words are addressed to the Assyrian invaders, but not without a side glance at all who had been weaving their own webs of policy instead of trusting in Jehovah. Scheme and result, conception and parturition, would be equally worthless.

Your breath, as fire ... — “Breath,” the hot panting of rage; this, instead of working the destruction of Judah, should prove suicidal.