Haydar Amuli belongs to the Hussayni Sayyid family and hails from the town of Amol, in Mazandaran, located in the north of present-day Iran, close to the Caspian Sea.

[2] In his early twenties, Sayyid Haydar Amuli returned to Amul and became a trusted confidant and eventually a special deputy and chamberlain to the Bavandid Hasan II, who was the ruler of Tabaristan.

Amuli quotes in his work Inner Secrets of the Path that he started to feel that he was corrupt and that he needed to move to a place where he could fully devote himself to God.

He abandoned the courtly life, a couple of years before Hasan II was assassinated by members of his own family.

Living in the village of Tihran, he began to follow a shaykh by the name of Nur al-Din Tihrani, a gnostic and ascetic of Allah.

[1] Eventually, Haydar Amuli went on to embark on a pilgrimage or Hajj, going on to visit various Shi'ite shrines and also traveling to Jerusalem as well as the holy cities of Mecca and Medina.

Pure monotheism is constituted by the profession of faith and of the idea of the outward aspect of God's unity.

[3] It is documented that Sayyid Haydar Amuli wrote over forty different works, but of those only seven remain.

al-Masāʾel al-āmolīya (or al-ḥaydarīya) is a work that consists of theological and juridical ideas that are addressed by Amuli written to his teacher Faḵr-al-moḥaqqeqīn.

"Indeed I swear by Allah that if the seven heavens were made of paper and the trees of the earth were pens, if the seas of the world were ink and the spirits, mankind and the angels were scribes, then they would be unable to write even a jot of what I had witnessed of the divine gnoses and realities" In Sayyid Haydar Amuli's commentary Al‑Muhit al‑A`zam (The Mighty Ocean, Amuli gives a brief family genealogy.

Scholars such as, Mir Damad, Mulla Sadra, Hadi Sabzavari, and Ayatollah Khomeini continued to establish a connection between Sufism and Shi’ism.