When a man is said to be searching for the Holy Grail within the mysteries, he is really looking for two things: his own spiritual essence and his own spiritual purpose. This in turn gives him the d rive from his spiritual self, which is necessary to carry out his particular part of the divine plan. Strangely enough, in searching for this innermost spiritual reality within himself (it sounds like a rather egocentric exercise) he is actually finding the nature of God, because in practice the two cannot be divided.
Essentially the search for the Holy Grail is a search for the most intense, inner reality of the individual. When you are looking for the Holy Grail outside, you are having a quest or adventure, and you are really seeking the type of experience that the spiritual nature actually needs. So all quests for the Holy Grail put the objective in a position where people have to overcome their own deepest fear to get the vision of that which is sought. It always hits at the weakest point. In practice the search for the Grail is really the quest for the self carried beyond the normal dimensions, and in looking within and finding the self, one has to find God because one is impossible without the other.
- The Story of Dion Fortune, pp. 125-6