Perhaps they lack the subtlety of other groups, but the Candles of God have no desire to be subtle. Perhaps they do not keep their secrets very well, but the Candles of God want their voices to be heard. Perhaps they are careless about who they kill, but there shall be no innocent bystanders when the fires of hell consume the unrighteous.
Magic is like alcohol, the more that is used, the more it causes a hangover later on and the less judgement one has when using it. If one waits a while after casting a spell, things "detoxify." A cantrip or two is like a sip of weak beer, whilst a large creation spell is like a bottle of vodka. Cast something too big and you can die from magic intoxication.