This phrase is the meaning of the word "Topheth." Topheth is a place in the Hinnom Valley, south of Jerusalem, where at one time people burned their children as sacrifices to a false god. (See: [[rc://en/ta/man/translate/figs-explicit]])
It is implied that this refers to the king of Assyria. This can be stated in active form. AT: "Yahweh prepared it for the king of Assyria" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-activepassive]])
# The pile is ready with a fire and much wood
"The pile is ready with much wood to make a fire"
# The breath of Yahweh, like a stream of brimstone, will set it on fire
This speaks of Yahweh's breath as if it were a river of fire that will set the pile on fire. (See: [[rc://en/ta/man/translate/figs-simile]])