The Shaykhís believed that since Muslims require the guidance of the Mahdi, there must be an individual on Earth who is capable of communicating with him. This personage would be described as the "perfect Shi'a", and Shaykh Ahmad was the first to adopt that position. Due to this unique capability, the leader of the sect attained a quasi-divinity in the eyes of his followers.
It is not clear whether it was Shaykh Ahmad or his successor, Sayyid Kazim Rashti, who predicted that the coming of the Mahdi was nearing.
"For Shaykh Ahmad, then, the Shi`ite learned man is not simply a mundane thinker dependent on nothing more than the divine text and his intellectual tools for its interpretation. The Learned must have a spiritual pole (qutb), a source of grace (ghawth), who will serve as the locus of God's own gaze in this world. Both pole and ghawth are frequently-used Sufi terms for great masters who can by their grace help their followers pursue the spiritual path. For Shaykh Ahmad, the pole is the Twelfth Imam himself, the light of whose being is in the heart of the Learned. The oral reports, he notes, say that believers benefit from the Imam in his Occultation just as the earth benefits from the sun even when it goes behind a cloud. Were the light of the Imam, as guardian (mustahfiz), to be altogether extinguished, then the Learned would not be able to see in the darkness.
" The symbol of the preexistent tree appears elsewhere in Shaykh Ahmad's writings. He says, for instance, that the Prophet and the Imams exist both on the level of unconstrained being or preexistence, wherein they are the Complete Word and the Most Perfect Man, and on the level of constrained being. On this second, limited plane, the cloud of the divine Will subsists and from it emanates the Primal Water that irrigates the barren earth of matter and of elements. Although the divine Will remains unconstrained in essential being, its manifest aspect has now entered into limited being. When God poured down from the clouds of Will on the barren earth, he thereby sent down this water and it mixed with the fallow soil. In the garden of the heaven known as as-Saqurah, the Tree of Eternity arose, and the Holy Spirit or Universal Intellect, the first branch that grew upon it, is the first creation among the worlds.
This notion of beings with both divine and ephemeral natures presages a similar doctrine of the Manifestation in the Babi and Bahá'í Faiths, religions whose origins are rooted in the Shaykhi spiritual tradition.
Siyyid Kázim did not explicitly appoint a successor. Rather, convinced that the Mahdi was in the world, he encouraged his followers to seek him out. Many of the Shaykhis expected Mullá Husayn, one of his favorite pupils, to take on the mantle. Mullá Husayn, however, declined the honor, insisting on obedience to Siyyid Kazim's final commands to go out in search of the Mahdi. Many of the followers of Shaykh Ahmad spread out as did Mullah Husayn. By 1844, two perspectives had emerged and camps arose based on the differing claims of two individuals.
Haji Karim Khan Kirmani became the leader of the main Shaykhi group that did not follow the Bab. He became the foremost critic of the Bab, writing four essays against him. Baha'u'llah in turn described Karim as "foolishness masquerading as knowledge Karim repudiated some of the more radical teachings of Ahsai and Rashti and moved the Shaykhi school back towards the mainstream Usuli teachings.
Bábis and then Bahá'ís see Shaykhism as a spiritual ancestor of their movement, preparing the way for the Báb and eventually Bahá'u'lláh. In this view Shaykhism has outlived its eschatological purpose and is no longer anymore relevant.
The current leader of the Shaykhiya is Ali al-Musawi, who heads a community with followers in Iraq - mainly Basrah and Karbala - Iran and the Persian Gulf. Basrah has a significant Shaykhi minority, and their mosque is one of the largest in the city holding up to 12,000 people. The Shaykhiya are resolutely apolitical and hence were allowed relative freedom under Saddam Hussein. Since the 2003 Invasion of Iraq and subsequent Iraqi Civil War they have been targeted by Iraqi nationalists who accused them of being Saudis on the grounds that Ahmad al-Ahsai was from present-day Saudi Arabia. They responded by creating an armed militia and asking all local political groups to sign a pact allowing them to live in peace. This was done at the al-Zahra conference in April 2006.
In Iran Shaykhism is regarded as the third Twelver Shi'a denomination after Usulism and Akhbarism. In their public explanations the Shaykhis have come so close to normative Usuli doctrine that Usulis have expressed some wonder at why the Shaykhis have maintained their separate existence.