Symbolism, Imagery, Allegory
When Ahaziah sends troops to arrest Elijah for predicting his death at the very beginning of kings, Elijah manages to evade these troops be pulling a nifty trick: he asks God to incinerate them. And so God does—twice, killing a total of fifty soldiers before telling Elijah to just go along peacefully. It's a quintessential moment of divine wrath, bringing on the full Disney fireworks extravaganza of death to make God's point.
Although in 2 Kings this is really just an opportunity for God to kill some enemies by demonstrating his superior firepower, "fire from heaven" has become a major symbol and sometime metaphor in world literature, up to the present day.
A good example is T.S. Eliot's "Little Gidding", where he contrasts the divine fire that inspires Jesus' disciples on Pentecost with the destructive fire that the Nazi bombs are spreading over London (where Eliot lived at the time). Eliot says that humans can either be consumed by the holy fire of love or the fire of their own hate: "The only choice or else despair / Lies in the choice of pyre from pyre / To be redeemed from fire by fire."