How do I warn a friend who sent religious chain emails?

I tend to be leery of emails that promise good things for passing on a prayer, and just quietly delete them. However, I received one recently that seemed to require a warning to the friends who are passing it on.

My question is, what general principles of faith can I use to show people they should not be placing stock in “pass it on to get blessings” email prayers? Do we have a Catholic equivalent of Snopes.com where one can check out messages such as the one I linked to? It seems to me an obvious fraud, but on what authority can I say for sure?

seekerz,

This link should give you some help in wording your letter to your friend. If you have any further questions or concerns that are not answered by this link, please contact Catholic Answers directly.

Recommended Reading:
How do you respond to chain letters?

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