Shaykh Ahmad ibn Zayn al-Dín ibn Ibráhím al-Ahsá'í (Arabic: شيخ أحمد بن زين الدين بن إبراهيم الأحسائي) (1753–1834), commonly known as Shaykh Ahmad or al-Ahsá'í, was a prominent 19th-century Muslim theologian and jurist who founded the influential Shaykhí school of Twelver Shiism, which attracted followers from throughout the Persian and Ottoman Empires.
He was a native of the Al-Ahsa region (Eastern Arabian Peninsula), educated in Bahrain and the theological centers of Najaf and Karbala in Iraq. Spending the last twenty years of his life in Iran, he received the protection and patronage of princes of the Qajar dynasty.
Shaykh Ahmad's teachings diverged from the Usuli school on key issues related to eschatology, the role of the ulama, and the proper interpretation of the mystical hadith of the Twelve Imams. These divergences resulted in accusations of heresy from orthodox members of the Shia ulama, and instances of persecution against Ahsá'í and his followers occurred during and after his lifetime.
Today, Shaykhí populations retain a minority following in Iran and Iraq. After the death of Shaykh Ahmad's successor, Kazim Rashti, many Shaykhís converted to Bábism and the Bahá'í Faith; the two Shaykhí leaders continue to be highly regarded by Bahá’ís, being seen as spiritual forerunners to that religion.
Little is documented about the early life of Shaykh Ahmad, except that he was born in Ahsa, in the northeast of the Arabian peninsula, to a Shi'i family of Sunni origin in either the year 1166 AH (1753 CE), or 1157 AH (1744 CE). Nabíl's Narrative, a Baha'i history, describes his spiritual awakening as follows:
While it is unclear how much of Nabil's interpretation is consistent with Shaykh Ahmad's true feelings, the underlying motivations for reform, and ultimately for messianic expectation, become somewhat clearer.
Shaykh Ahmad, at about age forty (1784 or 1794 - circa), began to study in earnest in the Shi'i centres of religious scholarship such as Karbala and Najaf. He attained sufficient recognition in such circles to be declared a mujtahid, an interpreter of Islamic Law. He contended with Sufi and Neo-Platonist scholars, and attained a positive reputation among their detractors. He declared that all knowledge and sciences were contained (in essential form) within the Quran, and that to excel in the sciences, all knowledge must be gleaned from the Quran. To this end he developed systems of interpretation of the Quran and sought to inform himself of all the sciences current in the Muslim world.
He also evinced a veneration of the Imams, even beyond the extent of his pious contemporaries and espoused heterodox views on the afterlife, the resurrection and end-times, as well as medicine and cosmology. His views on the soul posited a "subtle body" separate from, and associated with the physical body. It was this body that ascended into Heaven, he posited, when Muhammad was said to have bodily ascended, and this also altered his views on the occultation of the Imam Muhammad al-Mahdi. His views resulted in his denunciation by several learned clerics, and he engaged in many debates before moving on to Persia where he settled for a time in the province of Yazd. It was in Yazd that much of his books and letters were written.
Juan Cole summarizes the situation at the advent of the Shaykhi School, and the questions that were unfolding as his views crystallized and he acquired an early following:
Moojan Momen in his Introduction to Shi'i Islam (George Ronald, Oxford, 1985) states that many mujtahids were afraid that the Shaykh's preference for intuitive knowledge, which he claimed to obtain directly by inspiration from the Imams, would seriously undermine the authority of their position. Momen has some interesting and useful commentary on Shaykh Ahmad's doctrines and his succession during which the conflict with Shi'i orthodoxy intensified.
Shaykh Ahmad appointed Kazim Rashti as his successor, who led the Shaykhí movement until his death. He taught his students how to recognize the Mahdi and the Masih (the returned Jesus). After his death in 1843, many of his students spread out around Iraq and Iran to search for a new leader.
Shaykh Ahmad was a prolific writer, he is known to have completed 71 published works during his career, of which 354 contemporary manuscripts are known to be still extant. Writing primarily in Arabic, his work spanned a wide array of literary forms. The largest number of his works consist of correspondence with other members of the ulama or his students, usually intended to expand upon a teaching advanced in another work, or provide answers to vexing questions of theology or jurisprudence. Treatises and lessons composed independently by al-Ahsá’í make up a smaller number of his works, but tend to be longer than his correspondence and more commonly studied and reprinted. In keeping with Islamic and Persian literary and academic tradition, a large number of his works take the form of commentaries on Surahs from the Qur'an, important Hadiths of Muhammad or the Imams, or writing by earlier mystical or theological writers. The most comprehensive bibliography of Ahmad's known works identifies twelve wide subject areas addressed by individual works:
• Sharh al-Fawa'id. Lithographed. N.P. (Tabriz: 1856).
• Jawami' al-Kalim. Lithographed. N.P. (Tabriz: 1856-59).
• Sharh al-Masha'ir. Lithographed. N.P. (Tehran: 1861).
• Sharh al-'Arshiyya. Lithographed. N.P. (Tehran: 1861).
• Sharh al-Ziyara al-Jami'a al-Kabira. Chapkhaneh Sa'adat (Kirman: 1972), 4 Volumes.
• Rasa'il al-Hikma. Al-Da'ira al-'Alamiyya (Beirut: 1993).