book Al-Bahth wa al-Dalala fi Mushkil al-Risala (Investigation and Indication into the Obscurities of the Message):

"Likewise, regarding his saying—may Allah illumine his face—concerning what was mentioned in the Book about the story of Adam: in the exoteric sense (al-zahir), it is Adam addressed as the Father of Humanity. However, in the esoteric sense (al-batin), the one addressed regarding the disobedience, the Tree, the transgression by eating from it, and the fall from Paradise was Zayd bin Harithah, who is the first of the personages of the 'Informed Ones' (al-munba’in). Paradise here signifies Gnosis (al-ma‘rifa), according to the agreed-upon narration of the Khasibiyya sect."

In another aspect, it means: Paradise is Gnosis, luminosity, and purity. We have neither seen nor heard that Zayd bin Harithah fell from the Paradise which is Gnosis, nor from luminosity into humanity—nor did any of the personages of the Higher World (al-‘alam al-‘ulwi). Rather, they manifest with the manifestation of the Meaning (al-Ma‘na), the Name (al-Ism), and the Gate (al-Bab), and they disappear upon His occultation.

Since that is the case, the address concerning the disobedience, the Tree, the transgression by eating from it, and the fall from Paradise was [actually] fitting for us and directed at us returning [to us], for it is fitting for us; we fell from Paradise—which is luminosity—to the Earth, which is humanity, worldliness, and earthy bodies.