Selections From the Writings of `Abdu'l-Bahá
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135: According to the explicit decree of Bahá'u'lláh ...
 
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According to the explicit decree of Bahá'u'lláh one must not turn aside from the advice of a competent doctor. It is imperative to consult one even if the patient himself be a well-known and eminent physician. In short, the point is that you should maintain your health by consulting a highly-skilled physician.