His breath kindleth coals, and a flame goeth out of his mouth.
Kindleth coals - poetical imagery (Psalms 18:8, "There went up a smoke out of his nostrils, and fire out of his mouth devoured: coals were kindled by it").
Related Commentaries of Job 41:21
Job 41:21
21 His breath kindleth coals, and a flame goeth out of his mouth.