Re: He strikes a spark from a flint and then they bring the candles back to life
He would only have to light one single candle with the spark from the flint, then he could light all the other candles using the flame from the first one.
Having said that, I don't really find "bringing a candle back to life" very natural at all. I would simply say that he relit the candle.
He struck a spark with a flint to relight the candles, then tightly closed the window.
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