“When the oil burns, no angel can touch or pass through the flames, or he dies.”

What though the field be lost?
All is not lost; the unconquerable will
And study of revenge, immortal hate,
And courage never to submit or yield:
And what is else not to be overcome?
That glory never shall his wrath or might
Extort from me. 

 - John Milton, Paradise Lost; Book 1, lines 105 to 111