How does the author use foreshadowing in The Professor's House?

When St. Peter has his conversation with Appelhoff, the author is using strong foreshadowing. Appelhoff is an image of St. Peter — just as Appelhoff has spent his life hard at work in physical labor and has never had the time to think and reflect, St. Peter has spent his life hard at work in mental labor and has never had the time to think and reflect. St. Peter, having completed his life's work on the Spanish adventurers, is now coming to a time when he will, like Appelhoff, have time to think and reflect. This prospect frightens St. Peter at some level, because he will have to face himself, to encounter himself.