It would also have been permissible for us to believe in the tree of the bush and the fire, because He (the Almighty) appeared to Moses (peace be upon him) from the tree in the form of fire and spoke to him from it.

He struck many diverse parables to account for the numerous types of manifestations, states, attributes, and names that He brought into existence for His servants, corresponding to their diversity and conditions; so that we may know what each of these diverse things has of multiple parables corresponding to the plurality of their types. That is wisdom from a Wise One and knowledge from a Knowing One. These parables are only to indicate His (the Almighty's) existence to His servants, while in reality, the speaker has no word concerning Him, nor is there a limit for which parables can be struck, according to His saying:

{There is nothing like unto Him, and He is the Hearing, the Seeing} (Ash-Shura: 11).

Know, O noble brother... that the Creator (the Almighty) did not obligate the People of the Outward with the outward forms of these acts of worship and other outward matters except because of their lack of acknowledgment of the Inward and the intensity of their disbelief, cunning, rejection, and non-acceptance of the inward secrets.