Images of fire grab fast the attention of both those who seek God's swift revenge and those who don't believe it. The image, though, is God's alone. It is ours, then, to dissect, not second-guess, it. And the crux of fire does not appease entirely either prognosticating set. So let's void this analysis initially of case or cause and first address the simple truth that fire reveals.
Fire is powerful and all consuming.
Nothing met with fire survives unchanged. Fire must be lit, dependent upon a source. And fire begins at times from just a spark. Fire spreads uncontrollably. But most notably, perhaps, fire depends, for all these things, on an unassuming fuel.