Very sad implication.... (Spoiler)
I don't remember the quote verbatim, but when the kids are debating over whether or not to ask the "Scary German Guy" about translating the diary, one of them asks something to the effect of "How do you say 'Please don't kill me' in German?" At which point, the man himself appears off-screen behind them and speaks the quote in fluent German. A scene or two later, it's revealed that he knows about real "monsters" when his concentration camp tattoo is exposed.
The very first quote we hear from him takes on an entirely new context when you take into consideration that he may have spoken it or heard it spoken four decades earlier. German is his first language, but I don't think it's a coincidence that he's introduced speaking that line. This film has some rather deep implications to it at times.
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"In literature, it's called plagiarism. In the movies, it's homage" ~ Roger Ebert