Holy Guardian Angel
The oath of the Adeptus Minor includes a provision to "unite myself with my higher and Divine Genius", a process which is more commonly referred to (by way of Aleister Crowley) as Knowledge and Conversation of the Holy Guardian Angel. To undertake this process the Adeptus Minor must reconfirm the work of earlier grades (Zelator through Philosophus) with their newfound knowledge before passing to the Adeptus Major degree, as a full-fledged adept.