"Good for the body is the work of the body.
Good for the soul is the work of the soul.
Good for either is the work of the other."

Does anyone know the origin of this quote? A friend, the one I heard it from, opined it might be Thoreau, but she didn't know for sure. I've tried to find the source myself but evidently I'm not very good at researching such things. Suggestions welcome.

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