As the Gang was in what was left of Sunnydale and were talking about the Seed of Wonder, multiple demons started to emerge from the shadows. Willow was targeted by one of these demons and she was slammed against the wall and harshly interrogated about the whereabouts of the Seed. However, she was able to say the words to this spell and the demon who had her in his grasp burst into flame as Willow directed her magics to keep him at bay while he burns to death.
She cast a similar, non-verbal spell to save Xander from being attacked by a large demon during the battle at the entrance of the Deeper Well in England. Before the creature could do anything to him, Willow caused it to burn from the inside out, killing it and protecting Xander.