In response to your letter of 9 May 1989 in which you convey the request of one of the believers for information concerning the Tablet to a Physician revealed by Bahá'u'lláh, the following is an excerpt from a letter written on behalf of the beloved Guardian on this subject.
“The Tablet to a Physician was addressed to a man who was a student of the old type of healing prevalent in the East and familiar with the terminology used in those days, and He addresses him in terms used by the medical men of those days. These terms are quite different from those used by modern medicine, and one would have to have a deep knowledge of this former school of medicine to understand the questions Bahá'u'lláh was elucidating.
The translator of this Tablet therefore, if he is not to make serious errors, would "have to have a deep knowledge of this former school of medicine". Those portions of the Tablet that contain general guidelines for good health have already been translated into English and were published in "Star of the West", vol. XIII, no. 9 (December 1922) p.252, a copy of which was enclosed with your letter. Another and slightly different, English translation has been published in "Herald of the South", vol. 2, no. 4 (October-November 1927), p.1.
Although a copy of the original Tablet is on file at the World Centre, an approved translation is not yet available.
(Baha’i Library Online)