The king's fury appeared in his face, and in his words; taking this answer for the highest affront and provocation, which as the case stood he could not bear, the pride of his heart made his indignation boil over, and therefore he made the furnace seven times hotter. Tyrants would burn the people of God in hell if they could.
Related Commentaries of Daniel 3:19
Daniel 3:19
19 Then was Nebuchadnezzar fulle of fury, and the form of his visage was changed against Shadrach, Meshach, and Abednego: therefore he spake, and commanded that they should heat the furnace one seven times more than it was wont to be heated.