Zitat
と is often used without a suitable verb; with a verb of emotion, it might mean it's being said in that way. In this case, I think it means the quoted statement is being thought. Possibly whispered, but we don't really know that, we just might think that of someone that's looking up at the sky and wishing (praying?) for something to come true.
It could also be taken to mean 'looking up at the sky -as though to say- "If it comes true... "'
I'm less inclined to this interpretation only because we're already inside the head of the character with knowing about this wish held in his heart. If the rest of the sentence were purely external description it'd be different.
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