Disease and the Effects On the Soul

Scriptural Writings on Health and Healing

Know thou that the soul of man is exalted above, and is independent of all infirmities of body or mind. That a sick person showeth signs of weakness is due to the hindrances that interpose themselves between his soul and his body, for the soul itself remaineth unaffected by any bodily ailments. Consider the light of the lamp. Though an external object may interfere with its radiance, the light itself continueth to shine with undiminished power. In like manner, every malady afflicting the body of man is an impediment that preventeth the soul from manifesting its inherent might and power. When it leaveth the body, however, it will evince such ascendancy, and reveal such influence as no force on earth can equal. Every pure, every refined and sanctified soul will be endowed with tremendous power, and shall rejoice with exceeding gladness.
    

"Gleanings from the Writings of Bahá'u'lláh", rev. ed. (Wilmette: Bahá'í Publishing Trust, 1983)

Regarding your questions concerning the condition of the soul during illness: The passages in the "Gleanings" make it quite clear that physical ailments, no matter how severe, cannot bring any change in the inherent condition of the soul. As Bahá'u'lláh says: "The spirit is permanent and steadfast in its station".* The veil or hindrance that interposes between soul and body during physical disease is sickness itself. Sickness reveals a lack of balance in the human organism, an absence of equilibrium in the forces essential for the normal functioning of the human body. *[note: The words quoted here are from a translation appearing inBahá'í Scriptures. The passage as translated by Shoghi Effendi appears inGleanings, section LXXX,  as follows: "...the soul itself remaineth unaffected by any bodily ailments."]
    

In a letter written on behalf of Shoghi Effendi, 8 March 1936 to an individual believer