Irremediably corrupted through his constant association with Siyyid Muhammad, that living embodiment of wickedness, cupidity and deceit, he had already in the absence of Bahá'u'lláh from Ba_gh_dád, and even after His return from Sulaymáníyyih, stained the annals of the Faith with acts of indelible infamy. His corruption, in scores of instances, of the text of the Báb's writings; the blasphemous addition he made to the formula of the a_dh_án by the introduction of a passage in which he identified himself with the Godhead; his insertion of references in those writings to a succession in which he nominated himself and his descendants as heirs of the Báb; the vacillation and apathy he had betrayed when informed of the tragic death which his Master had suffered; his condemnation to death of all the Mirrors of the Bábí Dispensation, though he himself was one of those Mirrors; his dastardly act in causing the murder of Dayyán, whom he feared and envied; his foul deed in bringing about, during the absence of Bahá'u'lláh from Ba_gh_dád, the assassination of Mírzá 'Alí-Akbar, the Báb's cousin; and, most heinous of all, his unspeakably repugnant violation, during that same period, of the honor of the Báb Himself--all these, as attested by Áqáy-i-Kalím, and reported by Nabíl in his Narrative, were to be thrown into a yet more lurid light by further acts the perpetration of which were to seal irretrievably his doom.
Desperate designs to poison Bahá'u'lláh and His companions, and thereby reanimate his own defunct leadership, began, approximately a year after their arrival in Adrianople, to agitate his mind. Well aware of the erudition of his half-brother, Áqáy-i-Kalím, in matters pertaining to medicine, he, under various pretexts, sought enlightenment from him regarding the effects of certain herbs and poisons, and then began, contrary to his wont, to invite Bahá'u'lláh to his home, where, one day, having smeared His tea-cup with a substance he had concocted, he succeeded in poisoning Him sufficiently to produce a serious illness which lasted no less than a month, and which was accompanied by severe pains and high fever, the aftermath of which left Bahá'u'lláh with a shaking hand till the end of His life. So grave was His condition that a foreign doctor, named _Sh_í_sh_mán, was called in to attend Him. The doctor was so appalled by His livid hue that he deemed His case hopeless, and, after having fallen at His feet, retired from His presence without prescribing a remedy. A few days later that doctor fell ill and died. Prior to his death Bahá'u'lláh had intimated that doctor _Sh_í_sh_mán had sacrificed his life for Him. To Mírzá Áqá Ján, sent by Bahá'u'lláh to visit him, the doctor had stated that God had answered his prayers, and that after his death a certain Dr. _Ch_upán, whom he knew to be reliable, should, whenever necessary, be called in his stead.