I'm not sure that is true. And even if it would be true for Christianity, I'd guess the same could be said for Buddihsm [0]. Buddhism monks in particular seem to be a miserable lot, as they (try to?) never smile ... at least on photos as shown in temples in Thailand.
The core of Christianity, from my understanding, is to believe that Jesus died for your sins and through accepting Jesus (not through works) one is able to get to heaven. This I think is the defining contrast of Christianity with other major religions, as in Judaism, Hindusm, Buddhism, Islam and probably others good works are needed to get to a better afterlife or reach a final state (nirvana?).
Though please correct me if I am wrong in any of this, as I don't know all of every religion.
P.S.: I myself was born in The Netherlands, but for the last 7 years or so been living in Thailand.
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