Exodus 9:10

Exo. 9:10. The Egyptians had oppressed Israel in the furnaces in which they burnt their bricks, and now the ashes of these furnaces were made as much of a terror to them as ever they had been to the Israelites. These furnaces were a type of hell. God sends upon the wicked those plagues that are some participation of the misery and destruction of hell, are as a sprinkling of the ashes of that furnace upon them. Their consciences are scalded with the hot embers of hell-fire. Their boils and blisters were exceeding grievous, probably attended with extreme smart, like the continual scalding of the hot embers of a furnace. Therefore it is said the magicians could not stand before this plague. This sort of boil is called the botch of Egypt (Deuteronomy 28:27).