The ability of the human being to attain gnosis exists in his heart, not in any of his (other) faculties.  It is the heart that knows Allah and draws (ever) closer to Him.  It is the heart that acts for Allah and seeks Him.  The heart unveils what Allah contains and what the heart contains.  The faculties are no more than followers, servants and instruments used by the heart in the same manner in which a master uses his slave and a caregiver cares for his people and a craftsman utilizes his tools.